A chip that is of length L = 5.5 mm on a side and thickness t = 2.0 mm is encased in a ceramic substrate, and its exposed surface is convectively cooled by a dielectric liquid for which h = 150 W/m² K and T = 20°C. Th Chip, q. T., P. Cp The time is i Substrate In the off-mode the chip is in thermal equilibrium with the coolant (T; = T). When the chip is energized, however, its temperature increases until a new steady state is established. For purposes of analysis, the energized chip is characterized by uniform volumetric heating with q = 9 x 106 W/m³. Assuming an infinite contact resistance between the chip and substrate and negligible conduction resistance within the chip, determine the steady-state chip temperature Tf. Following activation of the chip, how long does it take to come within 1°C of this temperature? The chip density and specific heat are p = 2000 kg/m³ and c = 700 J/kg-K, respectively. The steady-state chip temperature T, is i S. °C.

A chip that is of length L = 5.5 mm on a side and thickness t = 2.0 mm is encased in a ceramic substrate, and its exposed surface is convectively cooled by a dielectric liquid for which h = 150 W/m² K and T = 20°C. Th Chip, q. T., P. Cp The time is i Substrate In the off-mode the chip is in thermal equilibrium with the coolant (T; = T). When the chip is energized, however, its temperature increases until a new steady state is established. For purposes of analysis, the energized chip is characterized by uniform volumetric heating with q = 9 x 106 W/m³. Assuming an infinite contact resistance between the chip and substrate and negligible conduction resistance within the chip, determine the steady-state chip temperature Tf. Following activation of the chip, how long does it take to come within 1°C of this temperature? The chip density and specific heat are p = 2000 kg/m³ and c = 700 J/kg-K, respectively. The steady-state chip temperature T, is i S. °C.

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 8.26P

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