Complete this problem pls ttempt in prConsider a power transistor encapsulated in an aluminum case that is attached at its base to a square aluminum plate of thermalconductivity k = 240 W/m-K, thickness L = 8 mm, and width W = 24 mm. The case is joined to the plate by screws that maintain acontact pressure of 1 bar, and the back surface of the plate transfers heat by natural convection and radiation to ambient air and largesurroundings at T = Tsur = 30°C. The surface has an emissivity of = 0.9, and the convection coefficient is h = 48 W/m².K. Thecase is completely enclosed such that heat transfer may be assumed to occur exclusively through the base plate.Ts.p =Your answer is partially correct.9max357.9iTransistorcaseTs,c, Pelec0.5992Enclosure -If the air-filled aluminum-to-aluminum interface is characterized by an area of Ac = 2 × 10-4 m² and a roughness of 10 μm and thesurface temperature of the case, Tsc, is not to exceed 85°C, determine the maximum allowable power dissipation, in W, and theassociated surface temperature of the power transistor, Tsp, in K.K0WL- Base plate, (k,e)-Interface, Ac-Ts.p111TsurAirTo h

The properties of air given condition is0

power transistor encapsulated in an aluminum case that is attached at its base yk = 240 W/m-K, thickness L = 8 mm, and width W = 24 mm. The case isj ssure of 1 bar, and the back surface of the plate transfers heat by natural conve gs at T = Tsur = 30°C. The surface has an emissivity of ε = 0.9, and the con pletely enclosed such that heat transfer may be assumed to occur exclusively t

power transistor encapsulated in an aluminum case that is attached at its base yk = 240 W/m-K, thickness L = 8 mm, and width W = 24 mm. The case isj ssure of 1 bar, and the back surface of the plate transfers heat by natural conve gs at T = Tsur = 30°C. The surface has an emissivity of ε = 0.9, and the con pletely enclosed such that heat transfer may be assumed to occur exclusively t

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.50P

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3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer coefficient on one side is and on the other side is . If the temperature of both streams is suddenly changed from 38°C to 93°C, determine how long it takes for the copper plate to reach a temperature of 82°C.
1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed to temperature of –5°C, while the inner surface is kept at 20°C. The thermal conductivity of the concrete is 1.2 W/m K. Determine the heat loss through the wall, which is 10-m long and 3-m high. Problem 1.1
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