HEAT TRANSFER
TUTORIAL 2
LU Jianjie
23/02/2016
Radiation
Radiation Stefan-Boltzmann Law
Emissive power:
Irradiation:
Absorbed irradiation:
Radiation exchange:
surrounding
irradiation
surface
emissive power
Resistance Model
conduction
convection
radia
1-D Steady Conduction w/ Eg
S. Yao MECH3310 Lecture 6 Ch 3.5 24/02/2016
1
For 1-D Steady Conduction w/ Eg, thermal circuit does NOT apply, must
solve the heat conduction equation.
Involves a local (volumetric) source of thermal energy due to conversion
f
MECH 3310 HEAT
TRANSFER
TUTORIAL 7 EXTERNAL CONVECTION REVIEW
HENRY LIYANTO
Outline
1.
Midterm Distribution and Paper Checking
2.
Homework 5 Problem 1
3.
External Convection and Lumped Capacitance Problem
4.
Extended Surface (Fin) Problem
Homework 5 Probl
Phase Change:
Boiling and Condensation
S. Yao MECH3310 Lecture 18 Ch. 10 15/04/2016
1
Boiling Heat Transfer
Evaporation occurs at
the liquidvapor interface
when the vapor pressure
is less than the saturation
pressure of the liquid at a
given temperature.
MECH3310 Spring 2016
S.Yao
Handout 7
Homework Assignment 6
Due: 15/04/2016
1. A 2-m-internal diameter spherical tank made of stainless steel (k =15 W/mK) in 1 cm
thickness is filled with iced water at 0C. The tank is located outdoors at 30C and is
subject
MECH 3310 HEAT
TRANSFER
TUTORIAL 5 FUNDAMENTALS OF CONVECTION
HENRY LIYANTO
Outline
1.
Discussion on Homework 4
2.
Solution to Quiz 2 in the Lecture
3.
Momentum and Thermal Boundary Layer
4.
Reynolds Analogy
5.
Similarity Analysis
Homework and Quiz Discus
MECH3310 Spring 2016
S.Yao
Handout 6
Homework Assignment 5
Due: 23/03/2016
1. The top surface of the passenger car of a train moving at a velocity of 70 km/h is 2.8 m
wide and 8 m long. The top surface is absorbing solar radiation at a rate of 200 W/m2,
a
2-D Conduction: Shape Factor
and Numerical Method
S. Yao MECH3310 Lecture 10 Ch 4 5.10 09/03/2016
1
Need to solve the heat equations for T (x,y)
For 2-D steady conduction, constant k, w/o Eg, derive the heat equation:
2T 2T
k 2 2 0
y
x
Solution Meth
Conduction: Fundamentals
S. Yao MECH3310 Lecture 3 Ch 1.3-1.4 12/02/2016
1
Fouriers Law
A rate equation that allows determination of the conduction heat flux
from knowledge of the temperature distribution in a medium
Its most general (vector) form for m
Internal Convection:
Energy Balance
S. Yao MECH3310 Lecture 15 Ch 8.3-8.4 06/04/2016
1
Determination of the Mean Temperature
Overall energy balance
Determination of Tm(x) is an essential feature of an internal flow analysis.
Determination begins with an
Convection Fundamentals:
Boundary Layers
S. Yao MECH3310 Lecture 11 6.1-6.4 11/03/2016
1
Physical Mechanism of Convection
Conduction and convection are similar in that both mechanisms require
the presence of a material medium.
But they are different in th
1-D Steady Conduction w/o Eg:
Radial System
S. Yao MECH3310 Lecture 5 Ch 3.3-3.4 19/02/2016
1
Radial Systems: Cylinder
For 1-D Steady Conduction w/o Eg,
T vary annularly, how to define CV?
0
E st E in E out E g 0
q
E in E out qr qr dr r dr 0
r
dT
dT
qr kA
Radiation Exchange and
Multimode Heat Transfer
S. Yao MECH3310 Lecture 23 Ch 13.3 04/05/2016
1
Radiation Shields
High reflectivity (low or ) surface(s) inserted between two surfaces for
which a reduction in radiation exchange is desired.
Two large parall
Radiation:
Radiation Intensity
S. Yao MECH3310 Lecture 19 Ch 12.1-12.2 20/04/2016
1
What are the differences of Radiation from Conduction and Convection?
Media not required
Spectral distribution
Directional distribution
S. Yao MECH3310 Lecture 19 Ch 12.1-
MECH3310 Spring 2016
S.Yao
Practice Midterm
Prepare for the Midterm
Time: March 30, Wednesday, 15:00-16:20
Location: 2303 (Surname starting with A-H); 2405 (J-N); 2504 (P-Z)
Closed book/lecture notes.
Prepare 1 sheet (two sides) of notes on standard A4 pa
Convection Fundamentals:
Similarity and Analogy
S. Yao MECH3310 Lecture 12 6.5-6.8 16/03/2016
1
Boundary Layer Similarity
As applied to the boundary layers, the principle of similarity is based on
determining similarity parameters that facilitate applica
MECH3310 Spring 2015
S.Yao
Handout 10
Homework Assignment 9
Due: 06/05/2016
1. A spherical incubator and the egg inside can be modeled as concentric spheres. The
incubator is 18 cm in radius with inc = 0.2, and T inc = 50 C. The egg has approximate
radius
Environmental Radiation
and
View Factor
S. Yao MECH3310 Lecture 21 Ch 12.8 13.1 27/04/2016
1
Interaction of solar radiation with earths atmosphere:
Absorption by aerosols over the entire spectrum.
Absorption by gases (CO2, H2O (v), O3) in discrete wave
TUTORIAL 10
SHANG Yuhe
26/04/2016
HOMEWORK 7 Q2
Need to verify natural convection can be negligible or not.
2
HOMEWORK 7 Q3
= ?
For horizontal plate, = =
For vertical plate, = 0.1
0.40.4
40.4
= 0.1
HOMEWORK 7
After determine
the flow is laminar
or turbu
MECH3310 Spring 2015
S.Yao
MECH3310 Heat Transfer
Final Exam 23/05/2015
16:30-19:30
1. (10 pt) A 2-m-internal diameter spherical tank made of stainless steel (k =15 W/mK) in 1
cm thickness is filled with iced water at 0C. The tank is located outdoors at 3
Internal Convection:
Hydrodynamic and Thermal
Considerations
S. Yao MECH3310 Lecture 14 Ch 8.1-8.2 01/04/2016
1
Hydrodynamic considerations
Hydrodynamic Effects: Assume laminar flow with uniform velocity profile at
inlet of a circular tube.
Velocity bou
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