A circuit board is cooled by passingcool helium gaş "C,= 5193 J/kg.C, v=1.233×10 m /s, p= 0.1635 kg/m Pr= 0.669, k = 0.1565 W/m.°C " through achannel [0.46 cm x14 cm×20 cm ]drilled into the board. Helium enters at15°C and 6.8 m/s and leaves at63.7 °C. The heat flux at the top surfaceof the channel can be considered to beuniform, and heat transfer throughother surfaces is negligible. Assumefully developed flow for the wholechannel length and (if flow is NOTLaminar use Dittus-Boelterequation:Nu=0.023 Re Pr) What isthe maximum surface temperature onthe circuit board (°C)?Electronic components,T, °CНе15°CL=20 cmChannel

Given: Cp=5193 J/kg°Cν=1.233×10-4 m2/sρ=0.1635 kg/mPr=0.669k=0.1565 W/m°CChannel dimension =0.46…

Answered: the maximum surface temperature on the…

Engineering

Mechanical Engineering

the maximum surface temperature on the circuit board (°C)?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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