3-202 A 0.2-cm-thick, 10-cm-high, and 15-cm-long circuit board houses electronic componernts on one side that dissipate a total of 15 W of heat uniformly. The board is impregnated with conducting metal fillings and has an effective thermal conductivity of 12 W/m-K. All the heat generated in the components is conducted across the circuit board and is dissipated from the back side of the board to a medium at 37C, with a heat transfer coefficient of 45 W/m2-.K. (a) Determine the surface temperatures on the two sides of the circuit board. (b) Now a 0.1-cm-thick, 10-cm-high, and 15-cm-long aluminum plate (k 237 W/m-K) with 20 0.2-cm-thick, 2-cm-long, and 15-cm-wide aluminum fins of rectangular profile are attached to the back side of the circuit board with a 0.03-cm-thick epoxy adhesive (k = 1.8 W/m K). Determine the new temperatures on the two sides of the circuit board. FIGURE P3-202 Electronic components Fin 15 cm L0.3 cm 10 cm 0.2 cm 20 fins mm 2 mm

3-202 A 0.2-cm-thick, 10-cm-high, and 15-cm-long circuit board houses electronic componernts on one side that dissipate a total of 15 W of heat uniformly. The board is impregnated with conducting metal fillings and has an effective thermal conductivity of 12 W/m-K. All the heat generated in the components is conducted across the circuit board and is dissipated from the back side of the board to a medium at 37C, with a heat transfer coefficient of 45 W/m2-.K. (a) Determine the surface temperatures on the two sides of the circuit board. (b) Now a 0.1-cm-thick, 10-cm-high, and 15-cm-long aluminum plate (k 237 W/m-K) with 20 0.2-cm-thick, 2-cm-long, and 15-cm-wide aluminum fins of rectangular profile are attached to the back side of the circuit board with a 0.03-cm-thick epoxy adhesive (k = 1.8 W/m K). Determine the new temperatures on the two sides of the circuit board. FIGURE P3-202 Electronic components Fin 15 cm L0.3 cm 10 cm 0.2 cm 20 fins mm 2 mm

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 2.32P

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Transcribed Image Text:3-202 A 0.2-cm-thick, 10-cm-high, and 15-cm-long circuit board houses electronic componernts on one side that dissipate a total of 15 W of heat uniformly. The board is impregnated with conducting metal fillings and has an effective thermal conductivity of 12 W/m-K. All the heat generated in the components is conducted across the circuit board and is dissipated from the back side of the board to a medium at 37C, with a heat transfer coefficient of 45 W/m2-.K. (a) Determine the surface temperatures on the two sides of the circuit board. (b) Now a 0.1-cm-thick, 10-cm-high, and 15-cm-long aluminum plate (k 237 W/m-K) with 20 0.2-cm-thick, 2-cm-long, and 15-cm-wide aluminum fins of rectangular profile are attached to the back side of the circuit board with a 0.03-cm-thick epoxy adhesive (k = 1.8 W/m K). Determine the new temperatures on the two sides of the circuit board. FIGURE P3-202 Electronic components Fin 15 cm L0.3 cm 10 cm 0.2 cm 20 fins mm 2 mm

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