Heat Transfer and Thermal Efficiency in Construction Technology

CONSTRUCTION TECHNOLOGY 5
By Name
Course
Instructor
Institution
Location
Date

Question 1
The body tries to keep a constants core temperature via creating a balance between the heat lost
and the heat gained. Body heat is often gained via activities including shivering as well as
exercise alongside the application of various external sources of heat including heat packs. There
are four major mechanisms through which heat is lost from the body including:
Radiation: The heat produced from the body is dissipated to the surrounding atmosphere through
vacuum
Evaporation: Evaporation of the liquid on the human body surface when an individual sweats or
dresses in wet clothes enhances loss of heat which in turn results in a cooling effect (Baglivo et
al., 2017).
Convection: Convection defines the process of flow of eater to air by the skin and tends to carry
away with it the heat of the body. It is loss in convective heat that one often attempts as much as
possible through keeping off water and water bodies. When left to stay still, the water boundary
layer adjacent to the skin gets heat by the body and maintains the undisturbed conditions. In case
there is movement around within the water, the boundary layer is disrupted of the warm water
which results in an increase in the loss of heat.
Conduction: There is conduction of heat to anything the body comes into direct contact.
Conductive heat loss takes place in cases where the skin is exposed to either cold water or air but
is often critical for the case of cold water since the heat loss by the body is approximately 25 fold
faster in water in comparison with air when taking place under same conditions of temperature.

Question 2
The flow of heat may be steady or even transient process. For the case of transient state, the flow
of heat and temperature change with changes in time while for the case of steady-state flow, the
flow of heat takes place when both the temperature and flow of heat get to a sable equilibrium
condition which does not change with changes in the time. Based on the specific problem, the
assumption made of steady state conditions may offer adequately accurate predictions of the real
heat flow as well as temperature conditions.
Heat transfer through the wall may take place in one, two or even three dimensions. In nearly all
the conditions, the flow of heat takes place in three dimensions even through from a practical
view point it is normally allowed to make the considerations simple ton just a single dimension
or series heat flow. Loss of heat from the building would occur in three main ways: