PROBLEM 1: The block of 304 stainless steel shown below is well insulated on the front and back surfaces, and the temperature in the block varies linearly in both the x- and y-directions. Find: (a) The heat fluxes and heat flows in the x- and y-directions. (b) The magnitude and direction of the heat flux vector. 15°C 5°C 5 cm 5 cm- 10 cm The thermal conductivity of 304 stainless steel is 14.4 W/m K. 10°C 0°C

PROBLEM 1: The block of 304 stainless steel shown below is well insulated on the front and back surfaces, and the temperature in the block varies linearly in both the x- and y-directions. Find: (a) The heat fluxes and heat flows in the x- and y-directions. (b) The magnitude and direction of the heat flux vector. 15°C 5°C 5 cm 5 cm- 10 cm The thermal conductivity of 304 stainless steel is 14.4 W/m K. 10°C 0°C

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 1.4P: 1.4 To measure thermal conductivity, two similar 1-cm-thick specimens are placed in the apparatus...

See similar textbooks

Similar questions

1.3 A furnace wall is to be constructed of brick having standard dimensions of Two kinds of material are available. One has a maximum usable temperature of 1040°C and a thermal conductivity of 1.7 W/(m K), and the other has a maximum temperature limit of 870°C and a thermal conductivity of 0.85 W/(m K). The bricks have the same cost and are laid in any manner, but we wish to design the most economical wall for a furnace with a temperature of 1040°C on the hot side and 200°C on the cold side. If the maximum amount of heat transfer permissible is 950 , determine the most economical arrangement using the available bricks.
1.4 To measure thermal conductivity, two similar 1-cm-thick specimens are placed in the apparatus shown in the accompanying sketch. Electric current is supplied to the guard heater, and a wattmeter shows that the power dissipation is 10 W. Thermocouples attached to the warmer and to the cooler surfaces show temperatures of 322 and 300 K, respectively. Calculate the thermal conductivity of the material at the mean temperature in W/m K. Problem 1.4
2.51 Determine by means of a flux plot the temperatures and heat flow per unit depth in the ribbed insulation shown in the accompanying sketch.
A section of a composite wall with the dimensions shown below has uniform temperatures of 200C and 50C over the left and right surfaces, respectively. If the thermal conductivities of the wall materials are: kA=70W/mK,kB=60W/mK, kC=40W/mK, and kP=20W/mK, determine the rate of heat transfer through this section of the wall and the temperatures at the interfaces. Repeat Problem 1.34, including a contact resistance of 0.1 K/W at each of the interfaces.
Question 5:Assume steady-state, one-dimensional heat conduction through the symmetric shape shown in Figure 1.Assuming that there is no internal heat generation, derive an expression for the thermal conductivity k(x) for these conditions: A(x) = (1 -x), T(x) = 300(1 - 2x -x3),and q = 6000 W, where A is in square meters, T in kelvins, and x in meters. Consider x= 0 and 1
Please provide accurate answer with proper steps The wall of the furnace is 30.48 mm thick and is insulated from outside. Thermal conductivity of the wall material is 0.1 W/m K and the insulation material is 0.01 W/m K. The furnace operates at 650 0C and the ambient temperature is 30 0 Allowable temperature on the outer side of the insulation is 1000C. Determine the overall heat transfer by conduction per unit area occurring across a furnace wall made from clay. If the air side heat transfer coefficient is 0.4 W/m2 K, calculate the minimum insulation thickness requirement.
2. In determining the thermal conductivity of a plateflat insulator, the temperature was measured on both sides of the 25 mm thick plate and gave the results of 318.4 K and 303.2 K. FluxThe measured heat is 35.1 W.m-2. Illustrate the problem in a simple schematic/drawing, then calculate the thermal conductivity inbtu/h.ft.oF and in W/m.K! (0.033 ; 0.058) 3. A coil-shaped cooling pipe is made of SS-304 material. This pipe is 1 ft long, 0.4 inch outside diameter, and inch inside diameter. This coil cooling pipe is used to cool the water in the bath. The temperature of the inner coil pipe is 40oF while the outer coil in contact with water is 80oF. The thermal conductivity of SS-304 is a function of temperature where k(T) = 7.75 + (7.78 x 10-3).T where k is in Btu/h.ft.oF and T is in oF. Calculate the rate of heat dissipation in watts! (1287.7)
1. A 240 mm dia. steam pipe, 200 m long is covered with 50 mm of high temperature insulation of thermal conductivity 0.092 W/m-K and 50 mm low temperature insulation of thermal conductivity 0.062 W/m-K. The inner and outer surface temperatures are maintained at 340°C and 35°C respectively. Calculate the following in Sl unit: a. the total heat loss per hour, b. the heat loss per m² of pipe surface, c. the heat loss per m² of outer surface,
Example 2.10 Consider a 25 mm x 25 mm x 1 mm thick silicon die attached to a same size 2 mm-thick copper cap through a 0.1 mm thick thermal interface material (TIM) as shown in Figure 2.1. Convection heat transfer coefficient on the top side of the copper cap is 2500 W/m²°C. If thermal conductivity of silicon, copper, and thermal interface material are 125, 390, and 5 W/m°C, respectively, what is the total thermal resistance from the active (bottom) side of the silicon die to outside ambient?
1. A 240 mm dia. steam pipe, 200 m long is covered with 50 mm of high temperature insulation of thermal conductivity 0.092 W/m-K and 50 mm low temperature insulation of thermal conductivity 0.062 W/m-K. The inner and outer surface temperatures are maintained at 340°C and 35°C respectively. Calculate the following in Sl unit: a. the total heat loss per hour, b. the heat loss per m² of pipe surface, c. the heat loss per m² of outer surface, d. the temperature between interfaces of two layers of insulation.
Mild steel nails were driven through a solid wood wall consisting of two layers, each 15 mm thick, for reinforcement. If the total cross- sectional area of the nails is 0.75% of the wall area, determine the unit thermal conductance of the composite wall, total heat flow, heat flow through the nail alone and the percent of the total heat flow that passes through the nails when the temperature difference across the wall is 35'C. Neglect contact resistance between the wood layers. Wood (Pine) (ky) = 0.15 W/(m K); Mild steel (1% C) (kg) = 43 W/(m K) а. ANSWER: W/m²-K b. ANSWER:
Experiment :LEE'S DISC Aim: To determine the thermal conductivity of a bad conductor by the Lee's method. What is the Analysis for this table and graph?