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Desklib is an online library for study material with solved assignments, essays, dissertations, and more. This case study analysis covers the fundamentals of mechanics, truss overview, stress-strain graph, fluid pressure measuring equipment, and fluid basics. The content includes subject B.Sc Combined Engineering, Mechanical Engineering Science, course code 107EN, and college/university Coventry University Group.

COVENTRY UNIVERSITY GROUP
CASE STUDY ANALYSIS
B.Sc Combined Engineering
Mechanical Engineering Science
107EN – Full Time Assignment
Student Name:
Student ID:

Contents
CASE STUDY A........................................................................................................
1. Case Study Fundamentals............................................................................
2. Exercise........................................................................................................
CASE STUDY B........................................................................................................
3. Truss Overview.............................................................................................
4. Stress-Strain Graph......................................................................................
CASE STUDY C........................................................................................................
5. Fluid Pressure Measuring equipment.........................................................
6. Fluid Basics..................................................................................................

CASE STUDY A
1. Case Study Fundamentals
(a) The fundamental of mechanics
The concept of mechanics is based on these three
fundamental quantities: mass, force and time along with
the three Newton’s law of motion. The latter is normally
the independent variable such that interaction of the
other two occurs within a predefined boundary designated
as space. For the purpose of simple analysis, particles and
objects are normally assumed to be moving on a rigid
plane hence two dimensional analyses is pursued.
Otherwise, in complex analysis, the three dimensional
analysis considers the motion of the object in all the three
basic directions. Mathematically, the directions are x, y
and z. Besides, the system of force equilibrium is often
considered and this is encapsulated by the three
fundamental laws of motion.
(b) Branches of mechanics
The major branches of mechanics are dynamics and
statics. The former mainly deals with motion of objects
and particles at rest or those moving with uniform velocity
throughout while the latter deals with motion of objects
that move with changing velocity over a given period.

Furthermore, in dynamics, there are two main sub
branches: kinetics and kinematics.
(c) Types of motions in mechanics
The basic types of motions include: Linear and non-linear
where the former deals with motion in a straight fashion
from point 1 to point 2 while the latter deals with motion
in a curvilinear manner such that the particle traces a
curved path on a plane or space
(d) The five SUVAT equations
S= Ut +1/2at2 .............(1)
V2= U2+2as.................(2)
V=U+ at......................(3)
S= Ut-1/2at2................(4)
S= t(u+v)/2 ................(5)
(e) Meaning of SUVAT
These are equations of linear motion in which acceleration
is assumed constant all over and in free fall case, often
acceleration value is same as value of gravity (9.81m/s2).
They often involve displacement S, velocity (both final V
and initial U), acceleration A and time t hence the
acronym SUVAT
(f) Components of a curvilinear motion
There are two components: tangential and normal
components. The former describes motion of particle such

that it is always orthogonal to the movement of particle.
The tangential component is parallel to the direction of
particle such that should it come off the curve, the particle
will trace this direction.
2. Exercise
Given:
The train engine at point E has a velocity of 20 m/s and an
acceleration of 14 m/s2 acting in the direction as shown in
figure 1
(i) The acceleration vector equation
This is given by: a= atut+ anun
(ii) The values of the tangential and normal components of
the acceleration
at=v’ut= 0.27601u2t2
an=(v2/ρ)un= 142/29.58= 6.626Un m/s
(iii) The value of ˙v from the tangential component of the
acceleration
v’=ut/at= 1/3.623 ut= 0.27601ut m/s2
(iv) The value of radius of curvature ρ (r) from the normal
component of the acceleration
ρ=[1+(dy/dx)2]1.5/ /d2y/dx2/ or we can use:
ρ=v2/an = 202/14sin75= 29.58 m
(v) The magnitude of the acceleration vector

The magnitude of acceleration vector is given by:
a= (at2+ an2)0.5
Now an= a sin 75= 14sin75= 13.522
And at= acos75= 14cos75= 3.623
Hence a= /13.5222+3.6232/0.5 = (13.1404+182.844)0.5 =195.980.5 = 13.99m/s2
CASE STUDY B
3. Overview of Trusses
(a) Description of truss
Truss is a rigid framework composed of rigid members
that are either in tension or compression and unitarily
supports structures such as roofing in buildings (Scribd, 2018).
(b) Truss Configuration

The two common configuration include: the pitched truss
which is triangular in basic shape while flat truss is
composed of parallel members as shown in figures 2(a)
and 2(b) below;
Figure 2(a): Pitched truss
Figure 2(b): Flat truss
(c) Condition for equilibrium
The basic criteria for static equilibrium in truss are:
(i) Sum of all forces in the x-direction must be zero;
similarly, sum of forces in the other two directions,
that is, y and z, must also be zero

(ii) Sum of moments in all directions must be zero, that
is, Sum of Mx=0, My=0 and Mz= 0
(d) Assumptions in truss analysis
It is assumed that the members are fixed to each other
and that there is buckling in members under stress, in
other words, they are rigid.
(e) Ways to determine if a truss is theoretical determinant
or in-determinant
In determinant case, the equations of statics are just
sufficient to determine the required parameters while in
in-determinant, there are extra theorems that must be
used to adequately define the system. For instance,
Castiglione’s theorem often comes in handy.
4. Stress-Strain Graph
Each test sample is 10 mm in diameter with a gage length of
50mm.

Figure 2: Engineering stress - strain graph
(a) Types of mechanical forces that can act on a body
(b) Definition of :
(i) Stress can be defined as the force acting per unit
surface area in an engineering material that
causes deformation or fracture. That is stress=
Force/Area (Engineeringtoolbox.com, 2018)
(ii) strain and the mathematical relationship between
them
Strain is the result of stress in materials such that
it designates the ratio of change in length to the
original length of material (Scribd, 2018).

The two are related as: Strain = Stress/Young’s
modulus that is έ = ϭ/E
(c) Material with the lowest yield stress is A. Its value is
320MPa
(d) Material with the lowest ultimate tensile strength is B.
Its value is 500MPa
(e) Material with a larger modulus of elasticity is B. Its
value= gradient (in the elastic region)=
(400-200)/(0.00025-0.0001)= 200/0.00015= 133.33GPa
CASE STUDY C
5. Fluid Pressure Measuring equipment
Critical analysis:
(a) The type of equipment to use in measuring the
pressure
A pressure transducer (capacitive) can be used to
measure the pressure as it easily integrates well
with the system that requires complex sensing to
optimize the flow process (Brighthub Engineering, 2018).
(b) Flow rate of the fluid (beer) during transportation
of the fluid (beer) from the production unit through
the pipe to the filler and coupling machine
Liquid flow meter can be used, it measures flow
rates in real-time and has a digital readout unlike
the conventional analogue types.

6. Fluid Basics
(a) Definition of Fluid
A fluid mainly designates liquid and gas states
such that they easily yield to pressure and move
freely without separation of mass of particles.
(b) Properties of Fluid
-Can easily flow under slight pressure changes
-In Newtonian Fluid, the pressure changes are
often assumed uniform
-Can easily be compressed
-Easily occupies the available space evenly
through flow (in liquid) and diffusion (gas)
-Fluid kinetic energy varies linearly as
temperature
(c) Real life application of some of these properties
-The car braking system is actuated via fluid
pressure transmission
-Compressed air is normally used to drive
systems in aircraft
-The hydraulic jack is used to lift heavy object
such as vehicles via fluid pressure mechanism.

(d) The equation of state as applies to fluid.
Thi is given by PV= mRT (in gaseous state).
References
Brighthub Engineering. (2018). Pressure Measurement Devices - Inclined Manometer, Bourdon
Gauge, Diaphragm Gauge, Bellows, Pressure Transducers, Electronic Pressure Sensors.
[online] Available at: https://www.brighthubengineering.com/hydraulics-civil-engineering/
43777-pressure-measurement-pressure-measurement-devices/ [Accessed 4 Apr. 2018].
Engineeringtoolbox.com. (2018). Stress, Strain and Young's Modulus. [online] Available at:
https://www.engineeringtoolbox.com/stress-strain-d_950.html [Accessed 4 Apr. 2018].
Scribd. (2018). Fundamentals of Engineering Mechanics | Force | Euclidean Vector. [online]
Available at: https://www.scribd.com/document/241787088/Fundamentals-of-Engineering-
Mechanics [Accessed 4 Apr. 2018].
Scribd. (2018). Trusses, Types, Configuration andConnections | Truss | Civil Engineering.
[online] Available at: https://www.scribd.com/document/115008353/Trusses-Types-
Configuration-and-Connections [Accessed 4 Apr. 2018].