Problems for Homework 3
Homework 3 is due on Thursday, 19th Feb by 10PM.
Graded problems
Q1. A 3-m-diameter spherical tank containing some radioactive material is buried in the ground
(k =1.4 W/mK). The distance between the top surface of the tank and th
7-37 A fan blows air parallel to the passages between the tins of a heat sink attached to a transformer. The minimum free-
stream velocity that the fan should provide to avoid overheating is to be determined
Assumptions 1 Steady operating conditions exist
Homework Problem: Application of ANSYS to a transient conduction problem
Due on March 5, 2015
Consider a 20 mm (0.020m) diameter sphere is initially at Ti = 330C. The sphere is suddenly immersed in an
ambience with heat transfer coefficient h=800 W/m2K an
3-97
3-143 The inner and outer surfaces of a long thick-walled concrete duct are maintained at specified temperatures. The rate of
heat transfer through the walls of the duct is to be determined.
30 C
Assumptions 1 Steady operating conditions exist. 2 Hea
Problems for Homework 5
Homework 5 is due on Thursday, 5th March by 10PM.
Graded problems (from Chapter 4)
Q1. Hailstones are formed in high altitude clouds at 253 K. Consider a hailstone with diameter of
20 mm and is falling through air at 15C with conv
Problems for Homework 7
Homework 7 is due on Thursday, 19th March by 10PM.
Graded problems (from Chapter 7)
Q1. A transformer that is 10 cm long, 6.2 cm wide, and 5 cm high is to be cooled by attaching a
10-cm x 6.2-cm-wide polished aluminum heat sink (e
Problems for Homework 4
Homework 4 is due on Thursday, 26th Feb by 10PM.
Graded problems (from Chapter 4)
Q1. In a meat processing plant, 2-cm-thick steaks (k = 0.45 W/mK and = 0.91 10-7 m2/s) that
are initially at 25C are to be cooled by passing them th
Problems for Homework 2
Homework 2 is due on Thursday, 12th Feb by 10PM.
Graded problems
Problem Numbers from 4th edition
Problem Numbers from 5th edition
2-91
3-49
3-65 (construct the thermal conduction network)
3-221
2-90
3-49
3-72
3-210
Clip of the pr
Homework Problem: Application of ANSYS to a transient conduction problem
Due on March 5, 2015
Consider a 20 mm (0.020m) diameter sphere is initially at Ti = 330C. The sphere is suddenly immersed in an
ambience with heat transfer coefficient h=800 W/m2K an
Problems for Homework 10
Homework 10 is due on Thursday, 23rd April by 10PM.
Graded problems (from Chapter 11)
Q1. A cross-flow heat exchanger consists of 80 thin-walled tubes of 3-cm diameter located in a
duct of 1 m X 1 m cross section. There are no fi
Problems for Homework 12
Homework 12 is due on Thursday, 30th April by 10PM.
Graded problems
Note - In these problems it may help to construct the thermal circuit.
Q1. [Chapter 13] This experiment is conducted to determine the emissivity of a certain
mate
3-79
3-123 Circular aluminum fins are to be attached to the tubes of a heating system. The increase in heat transfer from the tubes
per unit length as a result of adding fins is to be determined.
Assumptions 1 Steady operating conditions exist. 2 The heat
MAE 3240 Spring 2014
Homework 2 Due: Thursday, Feb 13th
3-26 A transparent lm is to be bonded onto the top surface of a solid plate inside a heated
chamber. For the bond to cure properly, a temperature of 70°C is to be maintained at the bond,
between the
MAE 3240 Spring 2014
Homework 4 Due: Thursday, Feb 27th I
3443 Consider a 25m-long thickwalled concrete duct (k = 0.75 W/m-K) of square cross
section. The outer dimensions of the duct are 20 cm X 20 cm, and the thickness of the duct wall
is 2 em. if the i
MAE 3240 Spring 2014
Homework 1 Due: Thursday, Feb 6th
2-25 Starting with an energy balance on a spherical shell volume element, derive the one-
dimensional transient heat conduction equation for a sphere with constant thermal conductivity
and no heat gen
MAE 3240 Spring. 2014
Homework 8 Due: Thursday, Mar 27th
8-39 Air at 10°C enters a 12cm-diameter and 5-m-long pipe at a rate of 0.065 kg/s. The inner
surface of the pipe has a roughness of 0.22 mm, and the pipe is nearly isothermal at 50°C.
Determine the
Homework 5 Due: Thursday, March 13th
,4
69 An average man has a body surface area of 1.8";rn2 and a skin temperature of 33°C. The
convection heat transfer coefcient for a clothed person walking in still air is expressed ash_=
8.6V3 for 0.5 < V < 2 In/s,