Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
8th Edition
ISBN: 9781305387102
Author: Kreith, Frank; Manglik, Raj M.
Publisher: Cengage Learning
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You are tasked to design a cooling system for an ice rink. A standard ice rink has surface area ofArink = 1580 m2 . In this design, a technologically advanced solid state thermoelectric generatingcooling plate is placed in between concrete slabs. The following diagram contains the dimensionalparameters of the design (a) In the space below, with your best effort to correspond to the above diagram, draw a thermalcircuit that establishes the relationship between the cooling plate’s heat rate, Q, and the system’stemperatures and thermal resistances. Label the appropriate dimensions, thermal conductivities,convection coefficient, and temperatures. Ignore effects from contact resistance. (b) Given that the temperature at the top surface of the ice must be T ice = -5°C, obtain the requiredheat rate Q that must be drawn by the cooling plate in units Kilowatts. Be careful of +/- sign.Answer: ____________________________ [kW] c) Using the thermal circuit you established in Part (a), obtain the…
****I hope that the solution is written on the computer and not written so that I can transfer it and understand it more quickly A composite wall of a refrigerator consists of three different materials; A, B, and C. Two of the used materials have known thermal conductivity, kA = 30 W/m. K and kC=45 W/m. K, and known thickness, LA=0.20 m and LC = 0.15 m. The third material, B, which is sandwiched between materials A and C, is of known thickness, LB = 0.15 m, but unknown thermal conductivity kB. Under steady-state operating conditions, measurements reveal an outer surface temperature of Ts,o = 20°C, an inner surface temperature of Ts,i = 600°C, and a refrigerator air temperature of T∞ = 800°C. The inside convection coefficient h is known to be 25 W/m2.K. (a) First, draw the thermal circuit for this wall. (b) What is the value of thermal conductivity for material B?
solve step by step and correctly. A family enters a winter vacation cabin has been unheated for such a long time the interior temperature is the same as the outside temperature (00C). The cabin consists of a single room of floor area 4m by 4m and height 3m. The room contains one 2kW electric heater. Assuming that the room is perfectly airtight and that all the heat from the electric heater is absorbed by the air, none escaping through the walls or being absorbed by the furnishing, how long after the heater is turned on will the temperature reach the comfort level of 240C.
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