MAE
problem4-27

# problem4-27 - PROBLEM 4.27 KNOWN Disc-shaped electronic...

• Notes
• 3

This preview shows pages 1–2. Sign up to view the full content.

PROBLEM 4.27 KNOWN : Disc-shaped electronic devices dissipating 100 W mounted to aluminum alloy block with prescribed contact resistance. FIND: (a) Temperature device will reach when block is at 27 ° C assuming all the power generated by the device is transferred by conduction to the block and (b) For the operating temperature found in part (a), he permissible operating power with a 30-pin fin heat sink. t SCHEMATIC: ASSUMPTIONS: (1) Two-dimensional, steady-state conduction, (2) Device is at uniform temperature, 1 , (3) Block behaves as semi-infinite medium. T P ROPERTIES: Table A.1 , Aluminum alloy 2024 (300 K): k = 177 W/m K. ANALYSIS: (a) The thermal circuit for the conduction heat flow between the device and the block hown in the above Schematic where R s e is the thermal contact resistance due to the epoxy-filled interface, ( ) 2 e t,c c t,c R R A R D 4 π ′′ ′′ = = ( ) ( ) 2 5 2 e R 5 10 K m W 0.020m 4 0.159K W π = × = The thermal resistance between the device and the block is given in terms of the conduction shape factor, able 4.1, as T ( ) b

This preview has intentionally blurred sections. Sign up to view the full version.

This is the end of the preview. Sign up to access the rest of the document.
• Spring '10
• LEE,J.S.
• Heat Transfer, fin, heat sink, 30-pin fin heat, fin array

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern