ANSWER THE QUESTION STEP BY STEP WITH FULL SOLUTION. NO CALCULATOR SHORTCUTS PLEASE. A 6 in thick concrete wall, having thermal conductivity k =0.50 Btu/h ft F, isexposed to air at 70°F on one side and air at 20°F on the opposite side. The heattransfer coefficients are h=2.0 Btu/h. ft² ° F on the 70°F side and =10 Btu/h.ft².0 F on the 20°F side. Determine the heat transfer rate

Given:thickness of wall, t=6 in =0.5ftThermal conductivity, k=0.50 Btu/h.ft.°FT1=70°FT2=20°Fhi=2.0…

A 6 in thick concrete wall, having thermal conductivity k =0.50 Btu/h-ft-º F, is exposed to air at 70°F on one side and air at 20°F on the opposite side. The heat transfer coefficients are h=2.0 Btu/h- ft² ° F on the 70°F side and h=10 Btu/h .ft².° F on the 20°F side. Determine the heat transfer rate

A 6 in thick concrete wall, having thermal conductivity k =0.50 Btu/h-ft-º F, is exposed to air at 70°F on one side and air at 20°F on the opposite side. The heat transfer coefficients are h=2.0 Btu/h- ft² ° F on the 70°F side and h=10 Btu/h .ft².° F on the 20°F side. Determine the heat transfer rate

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.1P: A plane wall, 7.5 cm thick, generates heat internally at the rate of 105 W/m3. One side of the wall...

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2.38 The addition of aluminum fins has been suggested to increase the rate of heat dissipation from one side of an electronic device 1 m wide and 1 m tall. The fins are to be rectangular in cross section, 2.5 cm long and 0.25 cm thick, as shown in the figure. There are to be 100 fins per meter. The convection heat transfer coefficient, both for the wall and the fins, is estimated to be K. With this information determine the percent increase in the rate of heat transfer of the finned wall compared to the bare wall.
2.2 A small dam, which is idealized by a large slab 1.2 m thick, is to be completely poured in a short Period of time. The hydration of the concrete results in the equivalent of a distributed source of constant strength of 100 W/m3. If both dam surfaces are at 16°C, determine the maximum temperature to which the concrete will be subjected, assuming steady-state conditions. The thermal conductivity of the wet concrete can be taken as 0.84 W/m K.
A plane wall, 7.5 cm thick, generates heat internally at the rate of 105 W/m3. One side of the wall is insulated, and the other side is exposed to an environment at 90C. The convection heat transfer coefficient between the wall and the environment is 500 W/m2 K. If the thermal conductivity of the wall is 12 W/m K, calculate the maximum temperature in the wall.
A cooling system is to be designed for a food storage warehouse for keeping perishable foods cool prior to transportation to grocery stores. The warehouse has an effective surface area of 1860 m2 exposed to an ambient air temperature of 32C. The warehouse wall insulation (k=0.17W/(mK)) is 7.5 cm thick. Determine the rate at which heat must be removed (W) from the warehouse to maintain the food at 4C.
1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a well-insulated 40-L tank of water that is initially at 300 K. If each heater dissipates 500 W, what is the time required for bringing the water temperature in the tank to 340 K? State your assumption for your analysis.
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Heat is transferred at a rate of 0.1 kW through glass wool insulation (density=100kg/m3) with a 5-cm thickness and 2-m2 area. If the hot surface is at 70C, determine the temperature of the cooler surface.
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Steam at 235°C is flowing inside a steel pipe (k = 61 W/m ∙ °C) whose inner and outer diameters are 10 cm and 12 cm, respectively, in an environment at 20°C. The heat transfer coefficients inside and outside the pipe are 105 W/m2 ∙ °C and 14 W/m2 ∙ °C, respectively. Determine (a) the thickness of the insulation (k = 0.038 W/m ∙ °C) needed to reduce the heat loss by 95 percent and (b) the thickness of the insulation needed to reduce the exposed surface temperature of insulated pipe to 40°C for safety reasons.