Five glass vials will be transported 4 hours stacked on top of each other in a hollow cylinder case. The glass vials have an initial temperature of -80 degrees, after the 4 hours transported in the cylinder case the temperature must not rise above -20 degrees. Each glass vial weighs 12.9g has a height of 38.7mm and and external diameter of 22mm. The first layer of the hollow cylinder is a polystyrene layer which is 20mm thick. There is then an insulation layer. Finally there is a 5mm thick steel layer, this has the temperature of the surrounding atmosphere of 22 degrees. What material and thickness should the insulation layer be to ensure the vials temperature does not increase above -20 degrees.

Five glass vials will be transported 4 hours stacked on top of each other in a hollow cylinder case. The glass vials have an initial temperature of -80 degrees, after the 4 hours transported in the cylinder case the temperature must not rise above -20 degrees. Each glass vial weighs 12.9g has a height of 38.7mm and and external diameter of 22mm. The first layer of the hollow cylinder is a polystyrene layer which is 20mm thick. There is then an insulation layer. Finally there is a 5mm thick steel layer, this has the temperature of the surrounding atmosphere of 22 degrees. What material and thickness should the insulation layer be to ensure the vials temperature does not increase above -20 degrees.

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.26P

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