Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470917855
Author: Bergman, Theodore L./
Publisher: John Wiley & Sons Inc
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Chapter 1, Problem 1.10P
A freezer compartment consists of a cubical cavity that is 2 mon a side. Assume the bottom to be perfectlyinsulated. What is the minimum thickness of styrofoaminsulation
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Problem 5.18: A furnace has inside dimensions of 1 m × 1.2 m × 1.5 m. The walls are 0.25 m
thick. The inside surface is at 750°C while the outside surface is at 80°C. If the conductivity of
the material is 0.45 W/mK determine the heat loss, taking into account the corner and edge
effects and also the bottom. (shape factors are taken from hand books).
h-1
1a.A copper slab (k = 372 W/m .K) is 3mm thick . it is protected from the
corrosion on each side by a 2 mm thick layer of stainless steel ( k = 17 W/m .K).
The temperature is 40°C on one side of this composite wall and 100°C on the
other. Find the temperature distribution in the copper slab and the heat
conducted through the wall.
Given:
ksteel = 17 W/m .K
kcopoer = 372 W/m .K
Steel Copper
T2
Steel
T1 = 40°C
T3
T4 = 10°C
2mm
3mm
2mm
A cold storage room has a wall consists of an inside finish of 0.60 in cement plaster(k = 0.67), two layers of corkboard each 2.5 in thick (k = 0.03) and an outside layer of building tile. The value of U for the entire wall is 0.058, the internal air filmcoefficient is 1.65, the inner temperature is 23°F and the outside temperature is85°F. Calculate the heat flow through the unit wall area, Btu/hr.ft2A. 1.47 B. 2.47 C. 3.47 D. 4.47
Chapter 1 Solutions
Fundamentals of Heat and Mass Transfer
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- The diagram below shows a composite wall 1 m deep. The first layer of thickness LA is made of special refractory material (kA=0.50 W/m.K). The second layer, 0.30 m thick, consists of insulating material A (kB=0.1 W/m.K) and insulating material B (kC = 0.35 W/m.K). The temperature on the inner face of A (Tsup) is equal to 900°C and the ambient temperature (Tamb) is equal to 25°C. The heat transfer coefficient h is equal to 10 W/m2.K. The rate of heat through the oven wall is constant and equal to 2500 W. Determine the thickness of the layer LA that forms wall A. What is the correct option? Present the calculation. a. 1,02 m b. 56 cm c. 27 cm d. 70 cm e. 12 cmarrow_forwardThe diagram below shows a composite wall 1 m deep. The first layer of thickness LA is made of special refractory material (kA=0.50 W/m.K). The second layer, 0.30 m thick, consists of insulating material A (kB=0.1 W/m.K) and insulating material B (kC = 0.35 W/m.K). The temperature on the inner face of A (Tsup) is equal to 900°C and the ambient temperature (Tamb) is equal to 25°C. The heat transfer coefficient h is equal to 10 W/m².K. The rate of heat through the oven wall is constant and equal to 2500 W. Determine the thickness of the layer LA that forms wall Aarrow_forward1a.A copper slab ( k = 372 W/m .K ) is 3mm thick . it is protected from the corrosion on each side by a 2 mm thick layer of stainless steel ( k = 17 W/m .K ) . The temperature is 40oC on one side of this composite wall and 100oC on the other. Find the temperature distribution in the copper slab and the heat conducted through the wall. Given: ksteel = 17 W/m .K kcopper = 372 W/m .K Steel Copper Steel T1 = 40oC T2 T3 T4 = 10oC q…arrow_forward
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