Radiation Heat Transfer
Introduction
Radiation DOES NOT require the presence of a
medium.
Unlike conduction and
convection, heat transfer
by radiation can occur
between two bodies,
even when they are separated
by a medium colder than
both of them.
Perso

Two-Dimensional Conduction:
Finite-Difference Equations
and
Solutions
Chapter 4
Sections 4.4 and 4.5
General Heat Conduction Equation
Finite-Difference Method
The Finite-Difference Method
An approximate method for determining temperatures at discrete
(no

CHE 4m FACULTY OF CHEMICAL ENGINEERING
HEAT TRANSFER UNIVERSITI TEIxNOLOGI MARA
; ; PAGE i : 1 i
Essex PLAN"
1.0 COURSE INFORMATION
COURSE NAME : HEAT TRANSFER
COURSE CODE : CHE 463
PROGRAM : EH220/221/222/223
CREDIT HOURS : 3
CONTACT HOURS : 4
COURSE S

Understanding Heat Transfer,
Conduction, Convection and
Radiation
Heat Transfer
Heat always moves from a warmer place to
a cooler place.
Hot objects in a cooler room will cool to
room temperature.
Cold objects in a warmer room will heat up
to room temp

HEAT EXCHANGER
EFFECTIVENESS-NTU METHOD
THE EFFECTIVENESS-NTU METHOD
The heat transfer in a heat exchanger will reach its maximum value when:
The cold fluid is heated to the inlet temperature of the hot fluid
Or
The hot fluid is cooled to the inlet temp

HEAT EXCHANGER
Types of Heat Exchanger
: Double-pipe Heat Exchanger
Two concentric tubes with one fluid flowing in the
inner tube and the other in flowing in the annulus.
a) Parallel Flow
b) Counter Flow
Types of Heat Exchanger
: Compact Heat Exchanger
D

Fundamentals of Convection
Heat Transfer
Objectives
Understand the physical mechanism of convection, and its
classification,
Visualize the development of velocity and thermal boundary
layers during flow over surfaces,
Gain a working knowledge of the di

External Forced Convection
Log Mean Temperature Difference (LMTD)
= =
=
=
=
=
=
= =
=
=
=
Friction factor, f and correction factor, x for tube banks
for in-line arrangement
Friction factor, f and correction factor,

Transient Heat Conduction
Lumped System Analysis
Some bodies are essentially isothermal and
can be treated as a lump system.
For an isothermal solid, the energy balance for
the time interval dt can be expressed as:
As
Heat Transfer
into the body
during

Energy Transfer
Heat thermal energy
Heat transfer transfer of thermal energy
Q amount of heat transferred during the
process
(Heat Transfer Rate) - amount of heat
transferred per unit time, J/s or W
=
0
when = constant
= t
Heat Flux, the rate of h

STEADY HEAT CONDUCTION
Objectives
Understand the concept of thermal resistance and its
limitations,
Solve steady conduction problems that involve multilayer
rectangular, cylindrical, or spherical geometries
Develop an intuitive understanding of thermal