Two coaxial parallel disks of equal diameter 1 m are originally placed at a distance of 1.5 m apart. If both disks behave as black surfaces, determine the new distance between the disks such that there is a 75% reduction in radiation heat transfer rate from the original distance of 1.5 m. (Round the answer to two decimal places.) The new distance between the disks = 1.31

Two coaxial parallel disks of equal diameter 1 m are originally placed at a distance of 1.5 m apart. If both disks behave as black surfaces, determine the new distance between the disks such that there is a 75% reduction in radiation heat transfer rate from the original distance of 1.5 m. (Round the answer to two decimal places.) The new distance between the disks = 1.31

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 1.24P: Two large parallel plates with surface conditions approximating those of a blackbody are maintained...

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1.28 The sun has a radius of and approximates a blackbody with a surface temperature of about 5800 K. Calculate the total rate of radiation from the sun and the emitted radiation flux per square meter of surface area.
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1.26 Repeat Problem 1.25 but assume that the surface of the storage vessel has an absorbance (equal to the emittance) of 0.1. Then determine the rate of evaporation of the liquid oxygen in kilograms per second and pounds per hour, assuming that convection can be neglected. The heat of vaporization of oxygen at –183°C is .
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