4–147 The thermal conductivity of a solid whose density andspecific heat are known can be determined from the relationk = a/pc, after evaluating the thermal diffusivity a.Consider a 2-cm-diameter cylindrical rod made of a samplematerial whose density and specific heat are 3700 kg/m' and920 J/kg-K, respectively. The sample is initially at a uniformtemperature of 25°C. In order to measure the temperaturesof the sample at its surface and its center, a thermocouple isinserted to the center of the sample along the centerline, andanother thermocouple is welded into a small hole drilledon the surface. The sample is dropped into boiling water at100°C. After 3 min, the surface and the center temperaturesare recorded to be 93°C and 75°C, respectively. Determine thethermal diffusivity and the thermal conductivity of the material.TaurfaceThermocouplesRodTeenterBoiling water100°C

Calculate the ratio of the dimensionless temperature difference. Here, is the surface temperature,…

20 J/kg-K, respectively. The sample is initially at a uniform emperature of 25°C. In order to measure the temperatures of the sample at its surface and its center, a thermocouple is nserted to the center of the sample along the centerline, and nother thermocouple is welded into a small hole drilled n the surface. The sample is dropped into boiling water at 00°C. After 3 min, the surface and the center temperatures re recorded to be 93°C and 75°C, respectively. Determine the

20 J/kg-K, respectively. The sample is initially at a uniform emperature of 25°C. In order to measure the temperatures of the sample at its surface and its center, a thermocouple is nserted to the center of the sample along the centerline, and nother thermocouple is welded into a small hole drilled n the surface. The sample is dropped into boiling water at 00°C. After 3 min, the surface and the center temperatures re recorded to be 93°C and 75°C, respectively. Determine the

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.32P

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