A 0.083 inch diameter electrical wire at 115◦F is covered by 0.02 inch thick plastic insulation with k = 0.075 (Btu/h.ft.◦F). The wire is exposed to a medium at 50◦F, with a combined convection and radiation heat transfer coefficient of 2.5 Btu/(h.ft2. ◦F). Determine if the plastic insulation on the wire will increase or decrease heat transfer from the wire.

A 0.083 inch diameter electrical wire at 115◦F is covered by 0.02 inch thick plastic insulation with k = 0.075 (Btu/h.ft.◦F). The wire is exposed to a medium at 50◦F, with a combined convection and radiation heat transfer coefficient of 2.5 Btu/(h.ft2. ◦F). Determine if the plastic insulation on the wire will increase or decrease heat transfer from the wire.

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 1.40P: As a designer working for a major electric appliance manufacturer, you are required to estimate the...

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