hot steam pipe (k-16 W/m K) has an inside and outside diameter of 80 mm and 190 mm. If the temperature of the steam is 523 K with h-3000 W/m²K and the outside temperature of the pipe is 353 K. If the pipe is 2 m long compelete the following the thermal resistance of heat transfer by convection is = the conductive heat resistance is the heat transfer per unit length is

hot steam pipe (k-16 W/m K) has an inside and outside diameter of 80 mm and 190 mm. If the temperature of the steam is 523 K with h-3000 W/m²K and the outside temperature of the pipe is 353 K. If the pipe is 2 m long compelete the following the thermal resistance of heat transfer by convection is = the conductive heat resistance is the heat transfer per unit length is

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 1.14P: Using Table 1.4 as a guide, prepare a similar table showing the orders of magnitude of the thermal...

See similar textbooks

Similar questions

Using Table 1.4 as a guide, prepare a similar table showing the orders of magnitude of the thermal resistances of a unit area for convection between a surface and various fluids.
As a designer working for a major electric appliance manufacturer, you are required to estimate the amount of fiberglass insulation packing (k = 0.035 W/m K) that is needed for a kitchen oven shown in the figure below. The fiberglass layer is to be sandwiched between a 2-mm-thick aluminum cladding plate on the outside and a 5-mm-thick stainless steel plate on the inside that forms the core of the oven. The insulation thickness is such that the outside cladding temperature does not exceed 40C when the temperature at the inside surface of the oven is 300C. Also, the air temperature in the kitchen varies from 15Cto33C, and the average heat transfer coefficient between the outer surface of the oven and air is estimated to be 12.0W/m2K. Determine the thickness of the fiberglass insulation that is required for these conditions. What would be the outer surface temperature when the inside surface of the oven is at 475C?
Show that the rate of heat conduction per unit length through a long, hollow cylinder of inner radius ri and outer radius ro, made of a material whose thermal conductivity varies linearly with temperature, is given by qkL=TiTo(rori)/kmA where Ti = temperature at the inner surface To = temperature at the outer surface A=2(rori)/ln(ro/ri)km=ko[1+k(Ti+To)/2]L=lenthofcyclinder
1.10 A heat flux meter at the outer (cold) wall of a concrete building indicates that the heat loss through a wall of 10-cm thickness is . If a thermocouple at the inner surface of the wall indicates a temperature of 22°C while another at the outer surface shows 6°C, calculate the thermal conductivity of the concrete and compare your result with the value in Appendix 2, Table 11.
1.2 The weight of the insulation in a spacecraft may be more important than the space required. Show analytically that the lightest insulation for a plane wall with a specified thermal resistance is the insulation that has the smallest product of density times thermal conductivity.
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. 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)
#m 3 E D C F3 $ 4 R F Ac = 1m² V Too,1=1 K h₁ = 1 W/m²K (5) Consider a wall (as shown above) of thickness L=1 m and thermal conductivity k-1 W/m-K. The left (x=0) and the right (x=1 m) surfaces of the wall are subject to convection with a convectional heat transfer coefficient h = 1 W/m²K and an ambient temperature T.= 1 K. Heat generation inside the wall is q=1W/m³. You may assume 1-D heat transfer, steady state condition, and neglect any thermal contact resistance. Find T(x). 44 % 5 Q Search F5 T G T₁ B x=0 * A 6 q=1 W/m³ k= 1W/mK L=1m F6 Y H F7 & 7 T₂ x= 1 m U N Top 2 = 1 K h₂=1 W/m²K PrtScn F8 8 Home M F9 ( 9 K End F10 0 L PgUp
GChoose the right answer 1. The temperature profile for steady hest conduction through a plane wall of constant thermal conductivity is a. logarithmic b. parabolic 2. A brick wall (k-0.75 W/mK ) transmits $02 of heat loss through another wall (k-0.25 W/mK, x-100 mm). If the temperature difference across both walls is the same, the thickness of the brick wall would be a.150 mm c. linear 6T b. 240 mm c. 300 mm d. 375 mm 3. The maximum temperature at the center of the solid sphere of radius R having heat generation q (W/m') is given by g'R +9R b. T, + 4k T+9R 6k d. T+9R 8k a. 2k C. 4. The internal thermal resistance of a solid can be ignored if the Biot number is less than a. 1 b. 0.5 c. 0.1 d. Fourier number 5. The ratio of heat transfer of a fin to the heat transfer without fin is referred to as a. fin resistance b. fin efficieney efin effectiveness d. fin conductance.
A furnace wall is constructed of a firebrick that is 6 inches thick. The temperature of the inside of the wall is 1300°F, and the temperature of the outside of the wall is 175°F. If the mean thermal conductivity under these conditions is 0.17 BTU/hr-ft-°F. What is the rate of heat loss through 10 square feet of wall surface?
yo lo:ll O %AV L. مرتضی نشط الآن Q5: The piston cylinder device (radius=10 cm) contains a liquid with a pressure 100 kpa and temperature of 20 ° C and has a liquid convection heat coefficient =93 WmK. Connect its fixed side to a cubic piece of aluminum (side length 15 cm) with a thermal conductivity coefficient of aluminum = 239 W mK. At the bottom of the aluminum piece there is a heat source with a temperature of 150 ° C, noting that the heat source is located in a vacuum chamber. Radiation thermal resistance = 3.17 K/W. Calculate the change in piston height during I sec. if you know that there is no change in the internal energy of the piston cylinder device. Note IK Watt 1KJ/s : Aa
The ceiling area of 100 square meters consists of four materials. The thermal insulation value of these materials from top to bottom is 1, 50, 0.6 and 0.45 square meters per watt per degree, respectively. If the outside temperature is O degrees and the internal temperature is 25 degrees, what is the speed Heat transfer through the wall?