To determine the thermal conductivity of a structural material, a large 6-in-thick slab of the material was subjected to a uniform heat flux of 800 Btu/(h ft2), while thermocouples embedded in the wall 2 in. apart were read over a period of time. After the system had reached equilibrium, an operator recorded the readings of the thermocouples as shown below for two different environmental conditions

From these data, determine an approximate expression for the thermal conductivity as a function of temperature between 100 and 400?F.GIVENThermal conductivity test on a large, 6-in.-thick slabThermocouples are embedded in the wall 2 in. apartHeat flux (q/A) = 800 Btu/(h ft2)Two equilibrium conditions were recorded (shown above)ASSUMPTIONSOne dimensional conduction

Transcribed Image Text:

Distance from the Surface (in.) Temperature (°F) Test 1 100 150 4 206 270 Test 2 200 265 335 406