A hot isothermal surface is to be cooled by attaching an array of parallel, equally spaced vertical square plates, side length =405 mm, AT between hot surface and surrounding air is 45°C and the film temp = 50 °C, Air properties (k = 0.02735 W(m.K, a =2.487E-5 m /s, v=1.798E-5 m /s, Pr= 0.7228). If the optimum spacing is 12 mm, what is the heat transfer rate (watts) from the 12-plates? 12 : number of plates. %3D Select one: A. 527.70 B. 469.65 C. 591.02 D. 638.52 E. 411.61

A hot isothermal surface is to be cooled by attaching an array of parallel, equally spaced vertical square plates, side length =405 mm, AT between hot surface and surrounding air is 45°C and the film temp = 50 °C, Air properties (k = 0.02735 W(m.K, a =2.487E-5 m /s, v=1.798E-5 m /s, Pr= 0.7228). If the optimum spacing is 12 mm, what is the heat transfer rate (watts) from the 12-plates? 12 : number of plates. %3D Select one: A. 527.70 B. 469.65 C. 591.02 D. 638.52 E. 411.61

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.21P: 1.21 In an experimental set up in a laboratory, a long cylinder with a 5-cm diameter, and an...

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hoday Septener A hot isothermal surface is to be cooled by attaching an array of parallel, equally spaced vertical square plates, side length -409 mm, AT between hot surface and surrounding air is 49°C and the flm temp-50 °C, Air properties (k= 0.02735 W/m.K, a=2.487E-5 m /s, v 1.798E-5 m /s, Pr=0,7228). What is the plate spacing (mm) that maximtzes heat transfer Trom the array?
A composite plane wall consisting of materials, 1.5-in steel (k = 312 BTU-in/HR.ft2.0F) and 2-in aluminum (k = 1400 BTU-in/HR.ft2.0F), separates a hot gas at Ti = 2000F, hi = 2 BTU/HR.ft2.0F, from cold gas at To = 80 deg F, ho = 5. If the hot fluid is on the aluminum side, find: a) Transmittance, U; b) The heat through 100 sq. ft of the surface under steady state condition and c) The interface temperature at the junction of the metals.
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