A new 1 ft thick insulating material was recently tested for heat resistant properties. The data recorded temperatures of 70 deg. F and 210 deg. F on the cold and hot sides, respectively. If the thermal conductivity of the insulating material is 0.026 Btu/ft . h .⁰ F, calculate the rate of the heat flux,Q/A, through the wall in Btu/ft^2 . h. Resolve the problem in SI units.

A new 1 ft thick insulating material was recently tested for heat resistant properties. The data recorded temperatures of 70 deg. F and 210 deg. F on the cold and hot sides, respectively. If the thermal conductivity of the insulating material is 0.026 Btu/ft . h .⁰ F, calculate the rate of the heat flux,Q/A, through the wall in Btu/ft^2 . h. Resolve the problem in SI units.

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 1.5P: To determine the thermal conductivity of a structural material, a large 15-cm-thick slab of the...

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To determine the thermal conductivity of a structural material, a large 15-cm-thick slab of the material is subjected to a uniform heat flux of 2500 W/m2 while thermocouples embedded in the wall at 2.5 cm. intervals are read over a period of time. After the system had reached equilibrium, an operator recorded the thermocouple readings shown below for two different environmental conditions: Distance from the Surface (cm) Temperature (C) Test 1 0 40 5 65 10 97 15 132 Test 2 0 95 5 130 10 168 15 208 From these data, determine an approximate expression for the thermal conductivity as a function of temperature between 40 and 208C.
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