Design of Waste Heat Recovery System for Hybrid Vehicle

This study focuses on designing a waste heat recovery system for hybrid vehicles. It aims to recover vehicle exhaust heat energy and convert it into electric power through the integration of the Rankine cycle. The study also analyzes the various modes of operation and forms of energy loss in a vehicle.

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Contents
ABSTRACT....................................................................................................................................................3
CHAPTER 1: INTRODUCTION........................................................................................................................4
1.1. Background.......................................................................................................................................4
1.2. Research Aims and Objectives..........................................................................................................6
1.3. Objectives of the Study.....................................................................................................................6
.4. Problem Statement.............................................................................................................................6
1.5. Rational of the Study........................................................................................................................7
1.6. Research Hypothesis.........................................................................................................................8
1.7. Thesis Outline...................................................................................................................................8
CHAPTER 2: LITERATURE REVIEW..............................................................................................................10
2.1. Introduction....................................................................................................................................10
2.2. Hybrid Vehicle Operational Modes.................................................................................................10
2.2.1 Theory of Operation.................................................................................................................11
2.2.1.1. Full stop................................................................................................................................11
2.2.1.2. Initial acceleration from a stop.............................................................................................11
2.2.1.3. Highway Driving....................................................................................................................11
2.2.1.4. Braking, Coasting and Deceleration......................................................................................12
2.3. Waste Heat Recovery.....................................................................................................................13
2.3.1. Regenerative & recuperative burners......................................................................................15
2.3.2. Economisers.............................................................................................................................16
2.3.3 Waste heat boilers....................................................................................................................16
2.3.4. Air preheaters..........................................................................................................................17
Benefits of Waste Heat Recovery System..............................................................................................18
Efficiency of HER & Cost Analysis...........................................................................................................19
Organic Ranking Cycle (ORC).................................................................................................................25
Principle of Operation of Organic Rankine Cycle...............................................................................26
Applications of ORC...........................................................................................................................27
Choice of Working Fluid.....................................................................................................................28
Applications of ORC in Waste Heat Recovery........................................................................................31
Heat Recovery on Industrial processes and mechanical equipment..................................................31
Heat Recovery on Internal Combustion Engine.................................................................................32

CHAPTER 3: RESEARCH METHODOLOGY...................................................................................................35
Theoretical calculations.....................................................................................................................37
CHAPTER 4: RESULTS & DISCUSSION.........................................................................................................40
CHAPTER 6: CONCLUSION.........................................................................................................................50
CHAPTER 7: REFERENCES...........................................................................................................................51

DESIGN OF WASTE HEAT RECOVERY SYSTEM FOR HYBRID VEHICLE
ABSTRACT
A device will be designed to recover vehicle exhaust heat energy and change to electric power
for the Hybrid vehicle. To achieve the above purposes, the invention is used to recover heat
energy from the exhaust gas and convert it into electrical power through the integration of the
Rankine cycle. The electricity generated by the Rankin cycle will be stored in batteries. It will
provide electrical energy to drive the vehicle or other devices on the vehicle. It includes some
accessories, such as motors, batteries, pumps, cooling systems, and heat exchangers. The project
will be designed in detail for specific exhaust pipes, including turbine design, generator
matching, and heat dissipation design and so on. This project will solve such challenges, such as
low energy conversion efficiency, difficult implementation, single-use, complex structure, large
volume and so on. Only after integration can commercial mass production is realized so as to
alleviate the rapid consumption of energy and reduce the rate of environmental pollution.

CHAPTER 1: INTRODUCTION
1.1. Background
Concerns regarding consumption of energy have remained to be on the increase in the
manufacturing industry. This has been as a result of the increase in the ecological adverse
outcomes as well as rise in the energy cost of production. Energy efficiency is one of the main
drivers of the automotive industry of today as it results in the industry delivering on
environmental as well as industrial performance. Energy efficiency has quickly shifted and
gained both national and international attention with various policies being developed both at the
regional as well as global levels aimed at curbing the worrying trend (Orr et al., 2016).
The great energy usage for operation of vehicles is significantly responsible for carbon dioxide
emissions and hence the witnessed changes in the climate. Taking into consideration that large
amount of this energy in the automotive industry is derived from fossil fuels there is fairness is
stating that carbon dioxide generated from the automotive industry also known as the automotive
industry carbon footprint have a very strong correlation with the efficiency of energy.
Nevertheless, the impact is proportional as the energy generated is consumed at the regional
levels while carbon dioxide emissions have worldwide impacts. There tends to be numerous
unnecessary use of energy in the industrial sector to the tune of between 20 per cent and 40 per
cent.
The prevailing trend of the automotive industry concentrates on maximization of the
performance of a vehicle as well as minimization of the fuel consumption alongside emissions
from the vehicle. Numerous technologies have been established dating back to the 1990s when
the global standard emissions began imposing boundaries on volumes of allowed emissions of
vehicles that led to always reducing volumes of emissions besides the consumption of fuel. Such

technologies are among them the addition of forced induction using supercharger and/or
turbocharger, using electric energy via high capacity batteries and even a combination of the two
(Kim et al., 2011).
The aim of this study is an examination of a vehicle technology that brings on board a
combination of aforementioned technologies that is termed as electric hybrid vehicle as well as
makes use of internal combustion engines using an electric power train as a component of the
propulsion architecture of vehicle, Since relatively large volume of fuel energy utilized in the
movement of any vehicle installed with internal combustion engine is often lost in the form of
heat, numerous systems have been established in exploiting the energy of the wasted heat in a
bid to provide it back to vehicle or engine in form of enhanced power or even as extra source of
electricity (Srinivasan, Mago and Krishnan, 2010). The organic Rankine cycle that is studied at
length in this study makes use of exhaust gases of engine in heating organic fluid and passing the
fluid via number of devices so as to generate electric or mechanical power that may then be used
in enhancing the different aspects of vehicle or engine performance.
The final lap of this study involves an evaluation of established hybrid model via 3 driving
cycles: New European Driving Cycle as well as two EPA federal examinations that are adopted
in the USA. The inspiration of this project is a derivative from the fact that very little research if
any has been carried out for use of organic ranking cycle waste heat recovery alongside a light
hybrid vehicle that is equipped with gasoline. The organic ranking cycle system is one of the
latest technologies that are yet to be adopted in lightweight vehicles and this is attributed not just
to the cost which is significantly high but also due to the lack of evidence offering proof that the
system may efficiently operate with engines having smaller capacity.

The study thus intends to evaluate the merits of implementation of an organic ranking cycle
waste recovery system as an aspect of the powertrain of a hybrid vehicle specially the reduction
potential of the fuel consumption (Sprouse and Depcik, 2013). For the same purpose, the
implementation of the organic ranking cycle systems would be tested through the use of two
most commonly used drive cycles to enhance the value of this assessment further hence resulting
in an increase in the utility and value.
1.2. Research Aims and Objectives
The main aim of this study is to design a waste heat recovery system for hybrid vehicle while
coming up with an implementation method of waste heat recovery system for electric hybrid
vehicles remains the major objective of the research.
1.3. Objectives of the Study
Other objectives of this study include:
 Investigating the various modes of operation of hybrid vehicles
 Conduct a literature review on organic Ranking cycle system
 Analyse the various forms of loss of energy in a vehicle and the modes of lowering the
losses
 Discussion waste heat recovery in the context of the performance of a hybrid vehicle
.4. Problem Statement
A device will be designed to recover vehicle exhaust heat energy and change to electric power
for the Hybrid vehicle. It will provide electrical energy to drive the internal combustion engine or
other devices on the car. Almost 70% of the chemical energy is wasted through engine exhaust
and cooling system. Serious and concrete efforts must be made to protect this energy through
waste heat recovery technology. Such a system would effectively cut down overall energy

requirements. Power in the cooling system is usually considered waste hence the research
focuses on the waste heat of exhaust gas, and several methods are suggested to recovery it. In
four-stroke engines, the temperature of waste gas is about 400-500 Centigrade.
Besides the consumption of fossil fuels, the combustion of these fuels makes much thermal and
environmental pollution, which threatens our ecosystem. Lots of fuel energy in the internal
combustion engine is treated as the waste gas. Only 25% of the heat generated by fuel
combustion is used for driving vehicles, while 40% of the energy is discarded by exhaust gas,
30% of the energy is released through coolant, and 5% of the power is transferred to friction.
That means the recovery of waste gas has excellent research potential.
1.5. Rational of the Study
The project is geared to improving the efficiency of the hybrid vehicle exhaust heat recovery
device. The project would solve such challenges among team low efficiency of energy
conversion, complex structure, difficult implementation, single use as well as large volume
among others. The number of electrical components that are found within a car system has
significantly increased aimed at enhancing the performance, convenience, comfort as well as
safety in the automobiles resulting in a sharp increase in the rated power of the on-board
generators including supply of automotive loads including electric steering system, air
conditioning, high energy discharge lamps as well as electric brakes. There is high power loss of
Rendel alternator is relatively high as a result of increased electric power that is used on the
vehicle. The 14V voltage level used in today's automobiles leads to an increase in current, which
leads to a thicker wiring harness. As a result, the cost of the whole power system increases while
the performance decreases significantly.

1.6. Research Hypothesis
Organic Rankine Cycle waste heat recovery system plays a major role in enhancing the
performance of a hybrid vehicle with regard to the energy efficiency.
1.7. Thesis Outline
The dissertation has six chapters as discussed below
Chapter 1: Introduction-The research topic is brought to limelight and a precise background
provided. The aim as well as objectives, research questions alongside significance of study is
highlighted. The main function if this chapter is to make known as well as brief reader of the
dissertation on what is availed in other chapters
Chapter 2: Literature review-Previous journals alongside works of other authors about waste heat
recovery, modes of operation of hybrid vehicles and organic Rankine cycle are discussed at
length. The main role of this chapter is to arm the researcher and reader with an elaborate
comprehension of the topic of the research.
Chapter 3: Methodology-The chapter is a discussion on approaches adopted in data collection
alongside various data collection methods used
Chapter 4: Discussions-The information that was obtained from literature review is elaborated
comprehensively with reference to research aims as well as objectives. In the chapter, answers to
research questions are sought
Chapter 5: Conclusion-This chapter offers study summary of the research conducted.
Recommendations and final remarks are included in this chapter

Chapter 6: References-All information sources of the data used in the dissertation are noted in
this chapter and such include books, journals, and articles among other sources which contain
relevant information to the research topic.

CHAPTER 2: LITERATURE REVIEW
2.1. Introduction
This chapter provides a discussion on previous journals and works of other authors regarding
waste heat recovery, modes of operation of hybrid vehicles and organic Rankine cycle are at
length. The main purpose of this chapter is to bring to light what previous experts have been able
to achieve as far as the research topic is concerned which would then provide a foundation on
which the current research and the solutions to the research questions are concerned.
2.2. Hybrid Vehicle Operational Modes
A hybrid electric vehicle defines hybrid vehicle type which brings together conventional internal
combustion engine system as well as electric propulsion system. The availability of electric
powertrain is aimed at attaining either enhanced fuel economy in comparison with conventional
vehicle or even better performance (Macián et al., 2013). There are numerous types of hybrid
electric vehicles and the extent of each function as an electric vehicle is as well variable. The
hybrid electric car is the most commonly used type of hybrid electric vehicle even though there
are as well hybrid electric Buse and hybrid electric trucks.
Modern hybrid electric vehicles adopt efficiency-enhancing technologies including regenerative
brakes that change the kinetic energy of the vehicle to electric energy that is stored in a super-
capacitor or a battery. Some types of hybrid electric vehicles make use of an internal combustion
engine to rotate an electric generator that either recharges the batteries of the vehicle or powers it
directly of the electric drive motors; a combination known as motor generator. Most of the
hybrid electric vehicles lower ideal emissions through switching off engine at idle as well as
restarting it in case there is need which are called as start-stop system. A hybrid electric
generates low tailpipe emissions in comparison with a sized gasoline car as the gasoline engine
of the hybrid is often smaller in relation to the gasoline powered vehicle. In case the engine is not

used in driving the car directly, it may be geared to operate at maximum efficiency hence
enhancing the economy of fuel (Jadhao and Thombare, 2013).
2.2.1 Theory of Operation
Hybrid cars may work differently based on the driving mode. The typical driving may be
grouped into four various modes. Knwoledge on how the hybrid vehicle works under very mode
is important in getting most gas mileage as well as minimizing the output of emissions. While
the car makers do not specify on the same, it is made to get super high gas mileage regardless of
how the driving is done. The four driving modes of hybrid vehicles as well as their theory of
operation are as discussed below:
2.2.1.1. Full stop
At a full stop just as is the case with a red light traffic or even a stop light, the gas engine often
closes down to remove idling as well as lower emissions. The electric motor is at the moment
ready in propulsion of the car when pushing on gas pedal. In densely populated cities having
numerous stop and go traffic this may save as far as fuel is concerned.
2.2.1.2. Initial acceleration from a stop
Beginning from a stop, the electric motor aids in accelerating the car with the power extracted
from the battery pack. In the case of downtown stop and go traffic one may save most of the fuel
with the use of hybrids as opposed to regular cars in which most of the fuel is burnt. The gas
engine switches off and on as required when one drives. Rapid acceleration would stull damage
the gas mileage just as is the case with conventional cars (Shabashevich et al., 2015).
2.2.1.3. Highway Driving
This is case in which fuel efficiency of a hybrid vehicle is not the same as a regular car. Lower
mileage is attained on the highway in comparison with the city. The backing behind is in the
driving mode car is basically powered only using gas engine that may be charging the electric

motor battery car simultaneously. Hence electric motor is not resulting during the highway
driving insinuating the hybrid is yet another gas powered car at highway speeds. Some of the
hybrids get relatively better mileage as compared to the non-hybrid counterpart since they can
used smaller and more efficient gasoline engine as the electric motor may aid in passing or
acceleration. Still, most of the hybrids have transmissions that are continuously variable enabling
the engine to work at optimal RPM (Boretti, 2012).
2.2.1.4. Braking, Coasting and Deceleration
The kinetic energy is converted to electric energy as opposed to being wasted in the form of heat
when one brakes or coast, as is the case with the conventional car. This is attained through the
use of the electric motor to act as generator that charges battery pack. The process of charging
battery is termed as regenerative braking. Hard braking needs normal friction brakes too hence to
attain the best fuel efficiency one needs to break smoothly.
When a vehicle moves on the surface of the road, there major driving modes may be noted:
traction mode, coasting mode as well as braking mode. The vehicle accelerates as well as the
force overcomes the inertia for the case of the traction mode while in braking mode vehicle
undergoes deceleration and the brakes release kinetic energy. The coasting mode on the other
hand defines the phase in which the vehicle is free-rolling in the absence of propulsive power
from engine or braking force from braking being provided. The same modes of operation are
applicable for hybrid electric vehicles even though a little bit more complicated since electric
motor extends extent of available modes of driving (Saidur et al., 2012). Still, there is difference
between modes of operation of series hybrid electric vehicle since their delivery of power
principle tends to differ.

Such operational modes are among them electric drive, engine drive, power split, hybrid as well
as braking mode all of which make use of the drive mode of the engine as propulsive mode upon
switching off electric motor. The electric drive mode makes use of just the electric motor in
providing motion of the vehicle even as the engine is disengaged. For the case of the hybrid
mode, the internal combustion engine as well as the electric motor is both used in driving the
vehicle. The engine provides motion as well as charges the battery pack for the case of the power
split mode. The braking mode is inclusive of the regenerative brake as well as the energy which
is kept in the battery to be used later (Javani, Dincer and Naterer, 2012). These modes maintain
the same principles of operations in series of hybrid electric vehicle even as differences depend
on the components which are used in every mode. The engine is disengaged from drivetrain and
is just connected to generator in series hybrid electric vehicle alongside the battery alone,
relocates power to traction motors.
2.3. Waste Heat Recovery
A large percentage of fuel energy in an internal combustion engine gets lost in the form of
exhaust gas heat, a fact which lowers the overall efficiency of the engine of conventional
vehicles. Ideal state of the art waste recovery technologies are among them mechanical or
electric turbo compounding, thermoelectric generators as well as bottoming cycles. A
mechanical turbo compound system makes use of the exhaust gas energy to turn a turbine that is
the linkable to the crankshaft providing more output power as well as to the tune of 5% enhanced
fuel economy.
An electric turbo compound setup on the other hand may be used in the exploitation of the
exhaust gas energy in gaining electrical power which may be saved in a battery or even used in
supporting numerous electric components of vehicle enhancing the fuel economy to the tune of

10% (Briggs et al., 2010). At the moment, about a 2% reduction in the consumption of fuel may
be offered by thermoelectric generators that make use of exhaust gas heat to generate electricity
directly through thermoelectric conversion means. The focus of this study is on the bottoming
cycle type of waste heat recovery that makes use of thermodynamic cycles in gaining energy out
of the exhaust gas heat. Such cycles operate using a working fluid alongside heat exchangers that
absorb the heat of the exhaust gases to turn the state of the fluid that is thereafter channelled
towards a turbine for generation of power.
The most commonly used thermodynamic cycles for such application are Rankine and Brayton
while this specific work is only on the Rankine cycle is considered as one of the most widely
acknowledged accepted as well as employed means of waste heat recovery. A basic parameter
which may foretell the efficient of waste heat recovery system is temperature of exhaust gases
and when the temperature is increased, the quality as well as amount of energy may be exploited
would as well enhance. Categorically, in the automotive industry the main kinds of vehicle
which may benefit from a waste heat recovery are mostly heavy-duty vehicles. Such vehicles
consume a lot of fuel besides generating large volumes of dangerous emissions among them
NOx and carbon dioxide gases.
The adoption of a waste heat recovery system in the vehicles may offer energy recovery benefits
in different forms which may further enhance the efficiency of the powertrain by about 10 per
cent to 15 per cent as well lower harmful emisions (Armstead and Miers, 2014).
There are numerous types of technologies that are used in waste heat recovery that are used in
the in the capturing as well as recovering of the waste heat and are mainly composed of energy
recovery heat exchangers that are in the form of a waste heat recovery unit. Such units are
majorly composed of waste heat recovery systems including air preheaters such as recuperates,

regenerators among them furnace regenerators and rotary regenerators or even heat wheel and
run around coil, heat pipe heat exchangers, economisers, regenerative and recuperative burners,
direct electrical conversion as well as plate heat exchangers among others.
2.3.1. Regenerative & recuperative burners
Regenerative & recuperative burners optimize efficiency of energy through the incorporation of
heat exchanger surfaces in the capturing and make use of the waste heat from hot flue flame
from the process of combustion. Regenerative devices are typically composed of two burners
having separate control valves that are connected to the furnace alongside alternatively heat the
combustion air that gets into the furnace. The working of the system is through guiding the
exhaust gases from furnace into a case that is composed of refractory material including
aluminium oxide. The exhaust gas is used in heating up the aluminium oxide media and the
energy of heat is recovered and stored from the exhaust. Upon full heating of the media, there is
a reversal in the direction of the flue gas where the stored heat is being transferred to inlet air that
enters the burners and burner with the hot media begins firing.
Figure 1: Recuperative burner structure

2.3.2. Economisers
Also known as finned tube, economisers are heat exchangers that are used in the recovery of low
to medium waste heat that are often used in heating of liquids. The system is composed of tubes
which are covered using metallic fins for the purposes of maximization of the surface area of
absorption of heat as well as the rate of heat transfer.
The system is place in the duct that carries the leaving exhaust gases and works by absorbing the
waste heat through allowing the hot gases to go through various sections covered using finned
tubes. Liquid is let through the tubes and it traps the heat from finned tubes. The hot fluid is the
fed back to system enabling attaining of maximization as well as improvement of the thermal
efficiency (Xie and Yang, 2013). Depending on a study carried out by Spirax Sarco, it is
demonstrated that suppose an economiser is used for a boiler system it may enhance the
efficiency by about 1% for each 5⁰C reduction of the temperature of flue gas.
2.3.3 Waste heat boilers
Waste heat boilers are composed of numerous water tubes which are put in parallel to each other
as well as in the direction of the heat that leaves the system. The system is ideal for the recovery
of heat from medium to high temperature exhaust gases and is often used in the generation of
steam as the main output. The steam may thereafter be used in the generation of power or
channelled back to system for recovery of energy.

Figure 2: Waste heat boiler schematic with parallel water tubes
2.3.4. Air preheaters
Air preheaters are mainly used in heat recovery of exhaust to air and mainly for low to medium
applications of temperature. The system is specifically crucial in cases where cross
contamination in the process has to be avoided and such applications may be inclusive of gas
turbine exhaust alongside heat recovery from ovens, steam boilers and furnaces. Air preheating
could be dependent on two varied designs: the heat pipe type as well as the plate type. The plate
type is composed of parallel plates which are put at right angles towards the incoming cold air
inlet. Feeding of hot exhaust air is done into the channels between the plates moving heat to the
plates hence resulting in hot channels which allow the passage of cold air. The heat pipe type is
composed of groups of numerous sealed pipes put in parallel to one another in a container. The
container is divided into two segments which accommodate hot and cold air, inlet as well as
outlet (Xie and Yang, 2013). The pipe within the container contains a working fluid that upon
being faced with the hot waste gas at an end of the pipe evaporates and shifts toward the other
end in which cold air passes.

Benefits of Waste Heat Recovery System
Both LDVs as well as HDVs utilize Internal Combustion (IC) engines, that generate a measure
of energy most of which is for the most part disseminated as heat via fumes gases furthermore,
coolant; separated from a little rate which may be for the most part helpful to be used for lodge
warming of utilizing the more energy expending A/C, energy might be recovered and utilized in
improving efficiency of powetrain. Figure below demonstrates a normal energy stream way of
interior burning motor where just 25 per cent of fuel burning is used for vehicle task, while
approximately 70 per cent of all-out fuel energy scatters to earth as heat misfortune principally
via vehicle exhaust system as well as radiator.
Figure 3: Energy flow in Internal Combustion engine
It is asserted transformation of 10 per cent of the waste heat to electricity by Rankine Cycle (RC)
framework or utilizing Thermoelectric Generator (TEG) may lead to the tune of 20 per cent in
increment of eco-friendliness, Saidur et al. (2012) therefore in decrease of emanations. The
benefits of utilizing TEG incorporate immaterial framework support, quiet task, high
dependability, and way that no moving as well as complex mechanical components are included
when contrasted with RC framework. For HDVs, fumes temperatures of gas extend from 200⁰C
to 500 °C under genuine conditions of driving, with a normal temperature of about 440 °C amid

thruway driving (Xie and Yang, 2013). Such temperatures may show significantly further
increment amid periodical recoveries of diesel particulate channel alongside other after-treatment
gadgets. Such high fumes temperatures give critical chances to Exhaust Heat Recovery (EHR)
framework to produce energy for expanding powertrain's productivity.
Efficiency of HER & Cost Analysis
Turbochargers and other as of late created systems of turbo-compounding are generally chosen
for exhaust waste energy recuperation of IC engines. Be that as it may, as expansion of fumes
back weight brought about by the turbine of turbocharger or turbo-exacerbating framework, the
framework effectiveness is undermined, contrasted with RC EHR framework. Then again, as
turbine needs a sufficient weight proportion, the fumes gas reasonable heat consumed by
turbocharger or turbo-aggravating framework is compelled and fumes temperature from turbine
is in every case still high as well a great deal reasonable heat remains. This permits EHR
framework still, obviously, to be installed downstream even turbocharger or turbo-exacerbating
framework has been introduced. EHR framework does not increment fumes back weight.
The advantages of utilizing EHR framework on fuel cost as well as discharges decrease have
been evaluated in Europe for traveller vehicles. The two reports show requirement for an entirety
life-cycle CO2 discharges way to deal with record for natural effects. In US life-cycle
investigation of overwhelming vehicles is being performed since though in Europe such sort of
examination is fairly constrained with data being specially appointed as well as concentrated on
findings created by singular EU Member States just.
As demonstrated in figure below Rankine Cycle EHR (RC-EHR) framework contains four
fundamental parts: evaporator/heat exchanger, expander, condenser as well as exhaust pipe. With
the evaporator/heat exchanger, working liquid is superheated by retaining heat energy given by

fumes gas. Streaming out from evaporator as high temperature steam, working liquid is driving
expander to deliver helpful work (Xie and Yang, 2013). The waste steam from expander is
thereafter chilled off through condenser and comes back to fluid structure. At long last, the
working liquid is siphoned to keep up the course. It must be noticed that expander is associated
precisely to generator that charges the battery of the vehicle.
Figure 4: (a) Rankine Cycle HER system; (b) TEG HER system (Xie and Yang, 2013)
Figure below demonstrates TEG EHR (TEG-EHR) framework that involves three fundamental
parts: thermoelectric generator, heat coupler to fumes pipe and a cooling coupling to motor
cooling tank. The temperature distinction between hot as well as cold surfaces of TEG prompts
present that might be utilized for charging of HDV battery.
For most IC motors, there is around a 20 per cent to 40 per cent of all out fuel energy, which is
scattered through fumes gas, most of which scatters as reasonable enthalpy because of high
fumes temperature while the rest as synthetic enthalpy because of deficient burning. To assess
the measure of energy that may be recuperated utilizing EHR framework, it is important to
acquire fumes temperature attributes under various conditions of driving. Suppose most truck

motors today keep running at about 1500 rpm at turning rate of 100 Km/h, fumes temperature
has mean estimation of 440 °C as well as under such condition the EHR framework efficiency
alongside recoverable energy sum are inspected straightaway (Xie and Yang, 2013).
Under such conditions, it is assessed roughly 3.9 per cent of fuel energy may be recouped by
RC-EHR framework. This is comparable to around 17.5 per cent of fuel utilization decrease. So
also, TEG-HER framework for diesel motors, joining new thermoelectric materials (for example
p-type tetrahedrites & n-type magnesium silicide) connected to class 8b trucks (mix tracks, for
example tractor-trailer, van, mass tanker, and so on) is required to recoup approximately 4 per
cent of fuel energy. This is proportionate to around 20 per cent of fuel sparing.
Figure 5: 9.7 lt engine exhaust gas specifications
Consolidating the previously mentioned EHR proficiency information, 20 per cent fuel
utilization decrease may be a fitting figure for speaking to most EHR frameworks that will be
utilized on HDV. With regards to present paper, an exact estimation technique for the expense of

Organic Rankine Cycle EHR framework has been inferred by thinking about normal
establishment costs go from 1,800 to 4,000 Euros for each kilowatt. Albeit distributed data on
real establishment expenses is constrained, one late report proposes that expenses could be
higher than 4,000 Euros for each kilowatt relying upon measure of application (Wang et al,
2011).
Figure 6, demonstrates with fixed fuel cost of 1.15 Euro/lt alongside a yearly mileage of 100000
Km, saving money on fuel cost by Hybrid trucks furnished with EHR framework is relied upon
to pay-back cost increment in 66 months, while traditional truck outfitted with EHR framework,
will pay in 12 months when 20 per cent eco-friendliness is accepted.
Figure 6: (3) powertrain configurations cost pay-back (diesel costs 1.15 Euros/lt & 20% fuel
efficiency) (Wang et al, 2011)
Figure 7, demonstrates with fixed fuel cost of 1.15 Euro/lt alongside yearly mileage of 100000
Km, saving money on fuel cost by Hybrid trucks outfitted with EHR framework is relied upon to
pay-back cost increment in 48 months, while a regular truck furnished with EHR framework,
will pay in 2 years, when 10 per cent eco-friendliness is expected. In any case, when fuel cost
increments by roughly 10 per cent to 1.25 Euro/lt, previously mentioned pay back occasions
increment to 5 and 1.5 years individually (Legorburu and Smith, 2019).

Figure 7: (3) powertrain configurations cost pay-back (diesel costs 1.15 Euros/lt & 20% fuel
efficiency) (Wang et al, 2011)
It is important to observe way an emotional increment of compensation time is normal when
yearly mileage is decreased from 100000 Km to 30000 Km, as appeared in Figure 8. The saving
money on fuel cost by Hybrid trucks furnished with EHR framework will pay back cost
increment in 114 months, while customary truck outfitted with EHR framework recompense in 5
years. This investigation demonstrates both yearly mileage as well as fuel cost vigorously
influence compensation back occasions.
Figure 8: (3) powertrain configurations cost pay-back (diesel costs 1.15 Euros/lt & 20% fuel
efficiency) (Wang et al, 2011)

Figure 9: (3) powertrain configurations cost pay-back (diesel costs 1.15 Euros/lt & 20% fuel
efficiency) (Wang et al, 2011)
The assessed pay-back occasions for CO2 emanations, of three HDVs under examination are
displayed in diagram 7. The two trucks outfitted with EHR framework could pay-back CO2
discharges in simply 15 months. As indicated by present investigation, in 56 months (for
example a mileage of 500,000 Km), a traditional truck furnished with EHR framework may
spare roughly 80,000 Kg of CO2 contrasted with Hybrid HDV furnished with an EHR
framework that demonstrates a normal sparing of 100,000 Km. This proposes trucks furnished
with EHR merit producing for money saving advantage and carbon discharge advantage,
specifically for high mileage HDVs.

Figure 10: (3) powertrain configurations CO2 emissions (diesel costs 1.15 Euros/lt & 20% fuel
efficiency)
Figure 11: (3) powertrain configurations CO2 emissions (diesel costs 1.15 Euros/lt & 20% fuel
efficiency) (Wang et al, 2011)
Organic Ranking Cycle (ORC)
The ORC framework utilizes progression of gadgets in loop circle so as to recuperate vitality,
which would then be able to be sustained back to engine or vehicle as needed. It comprises of
heat exchanger (evaporator) that hot gases go through as well as increment temperature of
working liquid to degree that it changes states from fluid to superheated vapor. After evaporator,
working liquid extends isentropically giving work in extension gadget, which is associated with
electric generator. At that point extended vapor goes through condenser to change its state back
to fluid and achieves siphon which builds its weight and drives working liquid back to
evaporator to rehash procedure (Wang et al, 2011). Figure below speaks to temperature-enthalpy
(T-S) chart of Rankine cycle, while subsequent outlines schematic perspective on organic
Rankine cycle with every single significant part. Hypothetically, the ORC frameworks can offer
a few advantages to entire powertrain design, best case scenario, and control yield of the
powertrain can be expanded by a limit of roughly 15% relying upon the application. As an

outcome of the expanded proficiency of the motor, the fuel utilization can be diminished, making
the ORC frameworks attractive for different applications.
Figure 12: Principles of operation of Rankine cycle: (a) temperature-enthalpy diagram; (b)
schematic Ranking cycle components (Shu et al., 2012)
Principle of Operation of Organic Rankine Cycle
The working guideline of the organic Rankine cycle is equivalent to that of Rankine cycle: the
working liquid is siphoned to heater where it is dissipated, gone through a development gadget
(turbine, screw, scroll, or other expander), and afterward through a condenser heat exchanger
where it is at long last re-dense. In perfect cycle portrayed by engine’s hypothetical model,
development is isentropic and dissipation and build-up procedures are isobaric. In any genuine
cycle, the nearness of irreversibilities brings down the cycle effectiveness. Those irreversibilities
mostly occur:
During expansion: Only piece of energy recoverable from weight contrast is changed into helpful
work (Shu et al., 2012)

 . The other part is changed over into heat and is lost. The proficiency of the expander is
characterized by correlation with an isentropic development.
 In heat exchangers: The working liquid takes a long and crooked way which guarantees
great heat trade however purposes weight drops that lower the measure of intensity
recoverable from the cycle. Similarly, the temperature contrast between the heat
source/sink and the working liquid creates exergy pulverization and decreases the cycle
execution (Song, Gu and Ren, 2016).
Applications of ORC
The Organic Rankine cycle innovation has numerous potential applications as well as tallies
more than 2.7 GW of introduced limit and 698 recognized power plants globally. Among them,
most across the board as well as promising fields include:
Organic heat recovery: Organic heat recovery is a standout amongst most significant
improvement fields for Organic Rankine cycle (ORC). It very well may be connected to heat as
well as power plants (for instance a little scale cogeneration plant on residential water warmer),
or to mechanical and cultivating procedures, for example, natural items aging, hot depletes from
broilers or heaters (for example lime and concrete ovens), vent gas build up, fumes gases from
vehicles, intercooling of blower, condenser of power cycle, and so forth (Espinosa et al., 2010).
Biomass power plant: Biomass is accessible everywhere globally and may be utilized for
generation of power on little to medium size scaled power plants. The issue of high explicit
venture costs for hardware, for example, steam boilers, are defeated because of low working
weights in ORC power plants (White et al., 2017). Another bit of leeway is long operational
existence of machine because of the qualities of working liquid, that dissimilar to steam is non-
dissolving and non-consuming for valve seats tubing as well as turbine sharp edges. The ORC

procedure additionally beats the generally little measure of information fuel accessible in
numerous locales in light of the fact that an effective ORC power plant is workable for littler
estimated plants.
Geothermal plants: Geothermic heat sources fluctuate in temperature between 50⁰C and 350
°C. The ORC is along these lines impeccably adjusted for this sort of utilization. Nonetheless, it
is imperative to remember for low-temperature geothermal sources (commonly under 100 °C);
efficiency is extremely low; depends emphatically on temperature of heat sink (characterized by
the surrounding temperature) (Crane and LaGrandeur, 2010).
Solar heat power: The organic Rankine cycle may be utilized in solar parabolic trough
innovation instead of standard steam Rankine cycle. The ORC permits control age at lower limits
and with a lower authority temperature, and subsequently the likelihood for ease, little scale
decentralized CSP units.
Choice of Working Fluid
The choice of working liquids has been treated in countless logical productions. By and large,
these examinations present a correlation between a lot of competitor working liquids as far as
thermodynamic execution and dependent on thermodynamic model of cycle (Van Kleef et al.,
2018). When choosing most proper working liquid, accompanying rules and markers ought to be
taken into consideration:
 Thermodynamic performance: Efficiency or potentially yield power ought to be as high
as feasible for given heat source as well as temperatures of heat sink. This exhibition
relies upon various related thermodynamic properties of working liquid: basic point,
acentric factor, explicit heat, density, and so on. It isn't clear to build up an ideal for every
particular thermodynamic property autonomously. The most well-known methodology

comprises in recreating the cycle with thermodynamic model while benchmarking
distinctive competitor working liquids.
 Positive or isentropic immersion vapor bend: as recently nitty gritty on account of water,
negative immersion vapor bend ("wet" liquid) prompts beads in the later phases of the
extension. The vapor should along these lines be superheated at turbine delta to stay away
from turbine harm (Nadaf and Gangavati, 2014). On account of positive immersion vapor
bend ("dry" liquid), a recuperator can be utilized so as to build cycle proficiency. This is
delineated in diagram below for isopentane, R11 & R12
Figure 13: Isentropic, wet & dry working fluids (Jabari et al., 2018)
 High vapor density: The parameter is of key significance, particularly for liquids
appearing low consolidating weight (for example silicon oils). A low density prompts a
higher volume stream rate: the sizes of heat exchangers must be expanded to confine
weight drops. This has a non-unimportant effect on expense of framework. It ought to
anyway be noticed bigger volume stream rates may permit more straightforward structure
on account of turbo expanders, for which size is anything but a critical parameter.
 Low density: low consistency in fluid as well as vapor stages leads to high heat exchange
coefficients as well as low grinding misfortunes in the heat exchangers (Imran et al.,
2019).

 High conductivity is identified with a high coefficient of heat transfer in heat exchangers.
 Adequate dissipating weight: as talked about for the instance of water as working liquid,
higher weights ordinarily lead to higher venture costs and expanded multifaceted nature.
 Positive consolidating check weight: the low weight ought to be higher than the climatic
weight so as to maintain a strategic distance from air invasion into the cycle (Boretti,
2012).
 High temperature strength: in contrast to water, organic liquids more often than not
endure substance crumbling and decay at high temperatures. The most extreme heat
source temperature is in this way constrained by the synthetic strength of the working
liquid.
 The dissolving point ought to be lower than most minimal encompassing temperature
during that time to abstain from solidifying of working liquid.
 High security level: safety includes two primary parameters—danger as well as
combustibility (Han et al., 2015). The ASHRAE Standard 34 characterizes refrigerants in
security gatherings and may be utilized for assessment of specific working liquid.
 Low Ozone Depleting Potential (ODP): the ozone draining potential is 11, communicated
regarding the ODP of the R11, set to solidarity. The ODP of current refrigerants is either
invalid or extremely near zero, since non-invalid ODP liquids are logically being
eliminated under Montreal Protocol (Wenzhi et al., 2013).
 Low Greenhouse Warming Potential (GWP): GWP is estimated regarding the GWP of
CO2, picked as solidarity. Albeit a few refrigerants can achieve GWP esteem as high as
1000, there is as of now no immediate enactment confining utilization of high GWP
liquids.

 Great accessibility and minimal effort: liquids effectively utilized in refrigeration or in
the compound business are simpler to acquire and more affordable.
Applications of ORC in Waste Heat Recovery
Heat Recovery on Industrial processes and mechanical equipment
Numerous applications in assembling business reject heat at generally low temperature. In
enormous scale plants, such heat is generally overabundant and regularly cannot be reintegrated
altogether on location or utilized for locale warming. It is along these lines rejected to air. This
results in two sorts of contamination: toxins (CO2, NOx, SOx, and HC) present in vent gases
produce safety as well as ecological issues; heat dismissal bothers sea-going harmonies and
negatively affects biodiversity (Sharafian and Bahrami, 2014). Recovering waste heat mitigates
the two sorts of contamination. It may in addition produce power to be expended nearby or
bolstered back to framework. In such framework, waste heat is generally recuperated by
moderate heat exchange circle and used to dissipate working liquid of ORC cycle. A capability
of 850 MWe is assessed for power age from modern waste heat in US, 500 MWe in Germany as
well as 3000 MWe in Europe (EU-12)
A few businesses present an especially high potential for waste heat recovery. One model is
concrete business, where 40 per cent of accessible heat is ousted via pipe gases. These vent gases
are situated after the limestone preheater or in the clinker cooler, with temperatures shifting
between 215 °C as well as 315 °C. CO2 emanations from the bond business sum for 5 per cent of
all-out world GHG outflows, and half of it is because of ignition of petroleum products in
furnaces. Different precedents incorporate the iron as well as steel enterprises (10 per cent of
GHG discharge in China for instance), treatment facilities and concoction projects (Hsieh et al.,
2017).

Heat Recovery on Internal Combustion Engine
An Internal Combustion Engine (ICE) just proselytes around 33 per cent of fuel energy to
mechanical power on run of the mill driving cycles: a regular 1.4 l Spark Ignition ICE, with a
heat efficiency going from 15 per cent to 32 per cent, discharges 1.7–45 kW of heat via radiator
(at temperature near 80 to 100 °C) as well as 4.6–120 kW by means of fumes gas (400⁰C to 900
°C).
The heat recovery Rankine cycle framework (both natural as well as steam based) is an effective
methods for recouping heat (in examination with different advances, for example, thermo-power
and retention cycle cooling) (Wang et al., 2011). The idea of applying Rankine cycle to an ICE
isn't new and primary specialized advancements showed up after the 1970 energy emergency.
For example, Mack Trucks structured and manufactured a model of such framework working on
the fumes gas of a 288 HP truck motor. A 400 km on-street test exhibited the specialized
possibility of framework and its affordable intrigue: a decrease of 12.5 per cent in the fuel
utilization was accounted for (Sakdanuphab and Sakulkalavek, 2017). Frameworks grew today
vary from those of 1970 in light of advances in the improvement of extension gadgets and the
more extensive decision of working liquids. Nonetheless, right now, no business Rankine cycle
arrangement is accessible.
A large portion of the frameworks being worked on recuperate heat from fumes gases and from
cooling circuit. On other hand, the framework created by just recuperates heat from cooling
circuit. An extra potential heat source is fumes gas distribution (EGR) as well as charge air
coolers, in which non-insignificant measures of waste heat are disseminated.
The output of the expander may be mechanical or electrical. With mechanical system, expander
shaft is legitimately associated with motor drive belt, with a hold to dodge control misfortunes

when ORC influence yield is excessively low. The primary disadvantage of such design is the
forced expander speed: this speed is fixed proportion of motor speed and is not really ideal speed
for augmenting cycle effectiveness. On account of power age, the expander is coupled to
alternator, used to refill batteries or supply assistant utilities, for example, cooling. It ought to be
noticed present vehicle alternators demonstrate a very low productivity (around 50 per cent to
60 per cent), which lessens ORC yield control (Horst et al., 2014).
With respect to the expander, the siphon can be legitimately associated with the drive belt, to
expander shaft, or to electrical engine. In last case, working liquid stream rate may be controlled
autonomously, which makes principle of such system lot simpler (Mirhosseini, Rezania and
Rosendahl, 2019). The control of system is especially intricate due to (regularly) transient
routine of heat source. In any case, advancing the control is critical to improve presentation of
system. It is commonly important to control both siphon speed and expander speed to keep up
needed conditions (temperature, weight) at expander delta.
Another specialized requirement is heat dissipation limit. The extent of front heat exchanger
(either an air-cooled condenser or even radiator associated with water-cooled condenser) is
restricted by accessible space and relies upon nearness of engine radiator, and conceivably a
charge air cooler, EGR cooler or even cooling condenser. The framework ought to be controlled
to such an extent that rejected heat stays inside cooling edge, characterized as the cooling limit
without working cooling fans. Something else, fan utilization may pointedly lessen net power
yield of framework (Mahmoudzadeh Andwari et al., 2017).
The exhibition of as of late created models of Rankine cycles is promising: framework structured
by Honda demonstrated most extreme cycle heat efficiency of 13 per cent. At 100 km/h, this
yields cycle yield of 2.5 kW (for a motor yield of 19.2 kW) as well speaks to expansion of motor

heat efficiency from 28.9 per cent to 32.7 per cent A contending innovation under innovative
work is thermoelectric generator (TEG), that depends on Seebeck impact: its primary favourable
circumstances are generously lower weight than ORC framework, and the nonattendance of
moving parts (Ji et al., 2018). Real downsides are the expense of materials (that incorporate
uncommon earth metals) and low accomplished effectiveness.

CHAPTER 3: RESEARCH METHODOLOGY
Research methodology defines the willingly approach that aids the researcher with the collection
of data that is deemed to be most appropriate and relevant or to conduct an analysis of the data
that is linked to his topic through the use of numerous strategies of research. The key aim of this
study if find out the design of waste heat recovery system for hybrid vehicle (Yang et al., 2015).
The research objectives and aims were determined to aid in the achievement of the study main
objective. To have an enhanced and wide comprehension of the research topic, there was need to
conduct a review to find out the design of waste heat recovery system for hybrid vehicle.
It was of great importance to have an understanding of the different characteristics of the topic of
the research. Hence qualitative approach alongside conducting a literature survey was utilized in
the course of the study. the chosen approach of research is very ideal in conducting this study as
the literature reviewed to be conducted offer in-depth data in find out as well as documenting
diverse variations in finding out the design of waste heat recovery system for hybrid vehicle.
The chosen research methodology offers a summary of the studies which were conducted on the
very topic and simultaneously offer a brief overview on establishing as well as documenting the
various changes in finding out the design of waste heat recovery system for hybrid vehicle. The
literature review was conducted to enable the researcher has a better comprehension of the topic
of the research as well as aid in the identification of the research gap (Amicabile, Lee and Kum,
2015).
Data Collection
Organic Rankine system has a strong ability to convert electricity from waste heat in the middle
and low grades and has many advantages with traditional Rankine system which uses water as
the fluid. Since the temperature of evaporator and condenser is constant, the energy and exergy

performance of the system will be better if the system operates at high boiler temperature (Shu et
al., 2017). Five different working fluids, R123, R600, R600a, R245fa, and R141b, were used as
working fluids. The energy and exergy performance of the system was analyzed when the
temperature of boiler, evaporator, and condenser changed in a certain time interval. From the
results, it can be readily understood that for a given parameter, R141b is the most suitable
organic fluid among the five different fluids. R245fa, an organic liquid commonly used in ORC
systems, seems unsuitable for this system because of its deficient performance compared with
R141b and R123. (Cihan and Kavasogullari 2017, 2622) A typical parameter for calculating the
efficiency of a waste heat recovery system is the temperature of the exhaust gas. The quantity
and quality of the available energy will increase following this temperature increase.
Table 1. Thermal physical properties of working fluids used in cycle

Theoretical calculations
Fig 2 Schematic diagram of Rankine cycle power generation for waste heat (Muszyński, 2017)
ηORC= ´Wturb
´Qboi+ ´W pump
´W turb=ηturb ,isen ηturb ,mec ´W turb ,isen
´Qboi= ´mORC ( h6−h5 )
´W pump= ´mORC ( h6−h5 )
ηpump
COPC = ´Qeva
´W comp
´Qeva= ´mref ( h1−h4 )
´W comp = ´Wc ,isen
ηC+ ηc ,isen
´Qcon=（ ´mref + ´mORC （ ( h8−h3 )

´W c , isen=ηstc ´W t , isen
ηstc=ηc , mec ηc, isen ηt ,isen ηt ,mec
ηsys= ´Qeva
´Qboi+ ´W pump
Ψ i=hi−h0− [ T 0 ( si−s0 ) ] (Specific exergy flow)
´Ei = ´mi Ψ i
I boi= ´mORC T 0 [s6 −s5− ( Qboi
T boi ) ]
ηe , boi=1− I boi
´E6− ´E5
I turb= ´E5− ´E7− ´W turb
ηe ,turb= ´Wturb
´E6− ´E7
I pump= ´E5− ´E3 + ´W pump
´
E5− ´E3
´W pump
ηe , pump=¿
¿
I comp= ´E2 − ´E1 + ´W comp
´
E2− ´E1
´W comp
ηe , comp=¿
¿

I mix= ´E2+ ´E7− ´E8
I eva= ´mref T 0 [s4−s1−
( Qeva
T eva ) ]
ηe , eva=1− I eva
´E4− ´E1
Icon= ( ´mref + ´mORC ) T 0 [ s3−s8−
( Qcon
T con ) ]
ηe , con=1− I con
´E8− ´E3
ηe , sys= ´Ec
´E❑
´Ec= ´E1− ´E4
´E❑= ´E6− ´E5+ ´W P

CHAPTER 4: RESULTS & DISCUSSION
This section provides a presentation of the findings from the simulations of ORC, giving an
analysis of the efficiency of the integrated systems as well as the points that need any
improvements in the entire systems. Finally, this section provides the exact values of the fuel
consumption of the vehicle respectively for each of the three various driving cycles and make up
the deciding factor for making a choice on the optimum hybrid profile as far as the integrated
powertrain is concerned. Numerous aspects which influence the efficiency of the Organic
Rankine Cycle system as well as how the system is joined with the Internal Combustion engine
to offer more power to wheels are evaluated in this section (Zhou et al., 2017).
It is of importance to highlight that the universal assumptions taken into considering for the
configuration of the Organic Rankine Cycle of the HEV train including in as much as the
backpressure as a result of the evaporator of the Organic Rankine Cycle put in the exhaust pipe
as well as the entire extra weight (Shi et al., 2016). This is as result of the Organic Rankine Cycle
components to the vehicle systems result in deterioration of the general performance alongside

fuel consumption of the vehicle to some degrees. In this investigation research of Organic
Rankine Cycle WHR systems for hybrid electric vehicles, an assumption has been made that the
impacts of these loads are negligible even though there is need to bear in the reader’s mind when
consideration is made to the results.
The main objective set for the findings of the analysis of Organic Rankine Cycle revolves around
the maximum efficiency of the turbine with the pump not bearing a percentage variation greater
than 15%. Still the turbine power output is as well very important since it is summed up with the
internal combustion engine power output to derive the cumulative power of the powertrain hence
it is need to be the highest possible (Muhammad et al., 2015). The rise in pressure in the pump is
yet another important parameter that is investigated in this analysis which shows the extent to
which the pump ascertains successful provision of the needed level of pressure throughout the
whole cycle. Lastly, the presentation of new BSFC map forms the conclusion of this section of
the improved powertrain with Organic Rankine Cycle. The efficient of the pump as well as the
distribution of the turbines are as shown in the table below over the engine load as well as speed
range subjected to test.
From the figures it can be noted of the kevel of fluctuation of the efficiencies of the two parts
with engine speed as well as the BMEP alongside the formation of the contours of constant
efficiency within the plot. The highest efficiency value of the turbine is estimated at 61% which
is determined at part-load even as the highest value of efficiency of the pump is found to be
72%at higher values of BMEP as well as speeds of engines. Attaining the highest efficiencies
called for expansion of great effort of the two components which led to an efficiency
improvement of about % from the first model (Tahani, Javan and Biglari, 2013).

turbine power output allocation is also demonstrated over the investigated engine loads and
speeds range where it can be moved the highest power is attained at full load as well as high
speeds since the exhaust gases are associated with greater temperatures as well as mass flow at
such speeds. The plot demonstrates the maximum power outputs produced by the turbines are
about 5 kW when the speed and load are high (Orr et al., 2016). At relatively lower speeds of the
engine s well s part load the turbine is able to produce figure about 2.5 kW. Such values may at
first sight seem small even though proved to be adequately high to result in a reduction in BSFC
of about 7% under the same conditions of operation.
The figure below offers information regarding the energy rate of the evaporators as well as the
rise in pump pressure respectively. BSFC reduction contour plots when superimposed on engine
map is as well illustrated when it may be interpreted from the given plot that the percentage
reduction in BSFC is different from various engine loads as well as speeds where the maximum
values for reduction have been noted low values of BMEP, that have generated as low as 12%
reduction (Lion et al., 2017). Besides, as there is an increase in the BMEP values at mid-load

range, the mean percentage reduction is about 7% that is much higher in comparison with the set
target. This region forms a region of utmost interest since most of driving time of the vehicle is
spent here hence the decrease by 7% in the consumption of fuel may significantly be of benefit
to the hybrid vehicle. When the value of BMEP is 9 bar and the engine loads high, there is a
lower reduction percentage on BSFC but often greater than 5% (Meng, Wang and Chen, 2016).

One last parameter which may be investigated about the Organic Rankine Cycle system regards
the system overall efficiency which generated the aforementioned BSFC reduction (Soffiato et
al., 2015). The Organic Rankine Cycle system efficiency refers to the portion of turbine power
output divided by the energy rate of the evaporator indicating the level of efficiency of use of the
energy that is present in the Organic Rankine Cycle system WHR system. Nevertheless, for the
case of this investigation, a four-cylinder 2000 cc was chosen, the present energy rate was
limited alongside the limitations within the system which were greater in comparison with a
bigger diesel engine which is capable of exploiting the entire system potential and reach even
greater efficiencies. The Organic Rankine Cycle system has been customized to provide the
highest possible efficient in a bid to mitigate this limitation (Bari and Hossain, 2013).
The distribution of Organic Rankine Cycle system efficiency is shown in the figure below
superimposed on engine map. It may be noted that generally, the efficiency of the Organic
Rankine Cycle system changes at various loads and speed engines alongside the values of
efficiency are not as high. At lower speeds of the engine as well as values of BMEP, the efficient
of Organic Rankine Cycle system gets to a maximum of about 27% which is not surprising as the
energy rate is significantly low while the simulated turbine power has at least already hot to
almost maximum values of efficiencies be it form lower efficiencies as well as loads. There is an
increase in the energy rates of the evaporator with an increase in the loads and speed engines
leading to a decrease in the efficiency since the turbine power does not increase proportionately
as a result of the restrictions within the Organic Rankine Cycle system design alongside the
exhaust temperature and rate of mass flow (Horst et al., 2013).
The efficiency of the ORC gets to an average figure of 10.5% when the engine speed is about
3000 rpm with the values of BMEP being 6.5 bars that is as well a significant region of operating

points of powertrain. More increase in speed of the engine as well as the values of BMEP
demonstrate an efficiency of about 9% that is the minimum that has be attained in this research
as well as for the whole engine range of operation. Generally, the ORC efficiency is of
importance even tho9ugh it is not getting to the full potential as a result of numerous inherent
limitation of the powertrain that has a small cavity (Zhang and Chau, 2011). Nevertheless, with
the given efficiency distribution, the ORC system can generate a mean decrease in the values of
BSFC of approximately 7% which is signficnt in comparison with the conventional HEV
configuration.
Hereinafter, the general consequences of the venture are further deciphered so as to get a
reasonable ORC WHR framework portrayal of its exhibition and advantage that it brings to the
ordinary HEV engineering. What's more, the talk shows how the diverse cross breed methods of
the vehicle ought to be picked so as to further diminish the fuel utilization of the vehicle;
explicitly, the talk recognizes which half and half mode ought to be picked in the diverse driving
situations, with the end goal that the vehicle can work all the more productively, while
expending the base measure of fuel.
Amid the different driving cycle tests that were performed in the motor reenactment
programming, the vehicle model was kept running with and without the ORC design, so the
outright contrast between these two setups could be recognized. In addition, the three distinctive
driving cycle tests can approve the proficiency of the entire powertrain in various driving
conditions, giving valuable data about the mixture mode which rises for each situation. At last,
these tests uncovered conceivable regions where the ORC framework could be additionally
advanced for more noteworthy HEV vehicle advantage. For the FTP-75 driving cycle test the

acquired information from the examination demonstrated that the fuel utilization of the vehicle
without the ORC framework was 9.74 L/100 km. At the point when the ORC framework was
incorporated into the powertrain, the new fuel utilization was determined to be 8.76 L/100 km,
which is just about 1 L less per 100 km.
Then again, on the NEDC, the outcomes demonstrated that the fuel utilization without the ORC
framework was 8.79 L/100 km, while when the ORC framework was incorporated into the
examination the new fuel utilization was 8.07 L/100 km. The contrast between these two
qualities is practically 0.8 L/100 km. The last driving cycle test was the US06, giving a fuel
utilization of 10.57 L/100 km without the ORC framework. At the point when the ORC
framework was included the investigation, the improved fuel utilization was diminished to 9.84
L/100 km, which is practically 0.7 L/100 km less. This driving cycle is more forceful than the
past two, which is the reason the powertrain achieved higher fuel utilization values in similar
terms to NEDC and FTP-75.
Also, the outcomes from the driving cycle investigation can help the comprehension of how the
ORC framework participates with the motor under various burdens, increasing velocities, and
decelerations. The three chosen driving cycles establish an agent case of driving guidelines being
used today and which were required to approve HEV execution with the novel segment (ORC
WHR framework). In Figure 5h the bar diagrams delineate the distinctions in fuel utilization
between the first HEV motor and the ORC-prepared proportionate so as to limit fuel utilization.
Moreover, the rate distinction is determined, with the goal that the total contrast of the improved
powertrain can be separated.
This bar graph incorporates data for each of the three of the driving cycle tests and presents the
definite measure of consumed fuel per 100 km of driving. It tends to be seen that in the majority

of the driving cycle situations, the fuel utilization was diminished after the usage of the ORC
framework. The biggest decrease was observed to be in the FTP-75 driving cycle and the
estimation of the high rate contrast demonstrated a 10% lower fuel prerequisite for 100 km. The
NEDC required minimal measure of fuel, as it isn't as forceful as the other two cycles. In
addition, in this driving cycle the ORC framework improved the fuel utilization by 8%, which is
a noteworthy decrease if the severe European guidelines are contemplated. At last, the US06
driving cycle required the most fuel generally speaking, however the ORC framework figured
out how to bring down the fuel utilization of the vehicle by 7%, which brought about a drop of
fuel utilization underneath 10 L/100 km.
A more critical investigation the three driving cycles was required to uncover the driving
procedure required in request to boost the powertrain execution in the electric mixture vehicle.
Considering the three noteworthy half and half task modes, which are the footing mode, braking
mode, and drifting mode, the driver can be guided in how to deal with the quickening agent
pedal, the braking pedal, and the grasp pedal to expand the productivity of the general vehicle.
To the extent the NEDC is concerned, it tends to be distinguished that it comprises of various
increasing velocities what's more, decelerations, and the normal cruising velocity is 60 km/h.
This driving cycle profile can abuse the braking and drifting activity methods of the half breed
setup to pick up Favorable circumstances with respect to the fuel utilization of the vehicle. Amid
the decelerations the brake ought to be delicately connected and this will prompt the battery
being charged by scattering the braking vitality and, thus, more power can be conveyed to the
wheels amid the speeding up zones. Additionally, the driver can utilize the drifting mode, while
no brakes or throttle are connected, before achieving the deceleration zones and counteract, in
that manner, the motor from consuming fuel in a non-helpful way.

The FTP-75 driving cycle has a convoluted profile of increasing speeds and decelerations, which
makes it hard for the driver to embrace the ideal driving technique. Notwithstanding, as there are
various variances in the speed profile of this cycle, the driver can misuse the braking mode to
charge the battery of the half breed setup. This picked up power can be utilized amid soak
increasing speed slopes to help crafted by the IC motor, prompting less fuel being singed amid
the various increasing speeds. For whatever length of time that there are no level speed districts
in this driving cycle, the drifting mode can barely be connected what's more, can't impact a
further decrease of the fuel utilization.
At last, the US06 driving cycle results show lower changes in the speed profile thought about to
the FTP-75, which implies that the drifting mode can be connected, offering noteworthy
advantages in fuel utilization decrease. This driving cycle drives the vehicle to achieve high
speeds of more than 120 km/h, which without a doubt builds the utilization of fuel of the vehicle.
So as to neutralize this, sensible utilization of the quickening agent pedal would be suggested,
alongside utilization of the intensity of the electric engine to help with noteworthy increasing
velocities. Then again, the braking mode can be used to accumulate the basic electric power in
the battery and the drifting mode can be utilized when the vehicle needs to diminish its speed
without the exacting utilization of the brakes.

CHAPTER 6: CONCLUSION
This project is used to improve the efficiency of the Hybrid vehicle exhaust heat recovery device.
A reenactment study has been directed to demonstrate that a waste warmth recuperation strategy
can be utilized in a half and half electric vehicle and offer critical advantages with respect to the
general execution of the vehicle, fundamentally as far as fuel utilization decrease. A natural
Rankine cycle-based waste heat recuperation framework was picked as the technique by which
to concentrate further work from the ordinary components of this half and half powertrain. In the
wake of using this framework in the powertrain, the outcomes demonstrated the generally fuel
utilization of the vehicle was diminished essentially. In the reenactment the motor was keep
running for three diverse driving cycle tests, including FTP-75, NEDC, and US06, so as to
approve the genuine improved execution of the created powertrain in various driving conditions,
and at last prompted a proficient driving methodology for the driver of the electric half breed
vehicle that could lower fuel utilization significantly further.

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