A thick-walled tube of stainless (A) having k=21.63 W/m.K with dimensions of 0.0254 m ID and 0.0508 m OD is covered with a 0.0254-m layer of asbestos (B) insulation, k=0.2423 W/m.K. The inside wall temperature of the pipes is 811K and the outside surface of the insulation is at 310.8 K. For a 0.305-m length of pipe, calculate the heat loss and also the temperature at the interface between the metal and insulation. (q = 331.7 W; T2 = 805.5 K)

A thick-walled tube of stainless (A) having k=21.63 W/m.K with dimensions of 0.0254 m ID and 0.0508 m OD is covered with a 0.0254-m layer of asbestos (B) insulation, k=0.2423 W/m.K. The inside wall temperature of the pipes is 811K and the outside surface of the insulation is at 310.8 K. For a 0.305-m length of pipe, calculate the heat loss and also the temperature at the interface between the metal and insulation. (q = 331.7 W; T2 = 805.5 K)

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.53P

See similar textbooks

Similar questions

A 112 m steel pipe has a 246.4˚C temperature, diameter of 230.8 mm is insulated with a 203.9 mm layer of asbestos and with a thermal conductivity of 0.424 W/m-K and followed by a layer of cork in 137.2 mm in thickness with a thermal conductivity of 0.35 W/m-K. If the ambient temperature of the cork is 120˚C. Calculate the heat loss. Answer: 25996.502359714 W
In order to reduce the heat loss through a large furnace wall, the decision has been made to add external insulation. Calculate the thickness of insulation required to reduce the heat loss by 75%. Before the change is made, no outer steel shell is used.Data: Refractory brick and wall brick:k = 0.87 W m-1 K-1Insulation: k = 0.090 W m-1 K-1•Steel: k = 43 W m-1 K-1h = 55 W m-1 K-1 (inside furnace).h = 11 W m-1 K-1 (outside furnace).
2. You have a 2.5 m x 10 m, R- 18 effective wall, that includes a window that is 4 m by 2 m that is installed with a window to wall transition details having a linear heat loss coefficient of 0.43 W/m·K. What would the adjusted opaque wall RSI-value be if you include the thermal bridging impact of the window to wall transition
It is required to insulate a kitchen oven with cork board (k = 0.043 W/mK) so that the heat losses from the oven does not exceed 400 W/m2 when the inner surface of the oven is at 225°C and the outer surface of the oven is at 40°C. The thickness of insulation required is nearly
What is the fin effectiveness of a rectangular plate fin made of aluminum O.3 mm thick mounted on a 16-mm-OD tube if the vertical tube spacing is 50 mm and the horizontal spacing is 40 mm? The air-side heat-transfer coefficient is 65 W/m2 • K, and the conductivity of aluminum is 202 W/m • K. Ans. ƞ is 0. 72 Please provide a comprehensive step by step solution on how to get the answer.
The wall of a refrigerator is made of fiberglass insulation (k = 0.035 W/mK) glued between two 1 mm thick layers of metal plate (k = 15.1 W/mK). The refrigerated space is kept at 2°C, and the average heat transfer coefficients on the inner and outer wall surfaces are 4 W/m²K and 9 W/m²K, respectively. The average temperature in the kitchen is 24°C. It is observed that condensation occurs on the external surface of the refrigerator when the temperature of the external surface drops to 20°C. Determine the minimum thickness of fiberglass insulation that should be used on the wall to prevent condensation on the outside surface.
A furnace wall is to consist in series of 7 in of kaolin firebrick, 6 in of kaolin insulating brick, and sufficientfireclay brick to reduce the heat loss to 100 Btu/ hr ft2 when the face temperatures are 1500 and 100°F,respectively.a) Show the figure of the systemb) What thickness of fireclay brick should be used?c) If an effective air gap of 1/8 in can be incorporated between the fireclay and insulating brick whenerecting the wall without impairing its structural support, what thickness of insulating brick will berequired?
The wall of a 5 m high cylinderical steel tank (ks= 20 W/mK) of inner diameter 1.5 m and 200 mm thick contains hot oil at 100 C. On the outside of the tank 12 mm of spray urethane insulation is added to stop the oil from cooling. If the worst outside temperature is -6 , (hi = 16 W/m^2 K) and (ho = 5 W/m^2 K) how much heat needs to be added to keep the tank at 100 C for pumping reasons and what are the overall heat transfer coefficients Uo and Ui?
The 5-mm-thick bottom of a 200-mm-diameter pan may be made from aluminum (k= 240 W/m·K) or copper (k= 390 W/m·K). When used to boil water, the surface of the bottom exposed to the water is nominally at 110°C and heat is transferred from the stove to the pan at a rate of 1200 W. What is the temperature of the surface in contact with the stove for each of the two materials?Aluminum:T= _____ °CCopper:T= _____ °C
A steel tube with 6 cm ID, 8.2 cm OD and k=18 W/m-C is covered with an insulative covering of thickness 3 cm and k = 0.3 W/m-C . A hot gas at 330 C with h = 400 W/m^2-C flows inside the tube. The outer surface of the insulation is exposed to cooler air at 28 C with h = 60 W/m^2-C. Calculate the heat loss from the tube to the air for 12 m of the tube and the temperature drops resulting from the thermal resistances of the hot gas flow, the steel tube, the insulation layer and the outside air.
A wall is constructed of two layers of 0.5-in-thick sheetrock (k = 0.10 Btu/h·ft·oF),which is a plasterboard made of two layers of heavy paper separated by a layer ofgypsum, placed 7 in apart. The space between the sheetrocks is filled with fibreglassinsulation (k = 0.020 Btu/h·ft·oF). Determine a) the thermal resistance of the wall, andb) its R-value of insulation in English units.
Finned heat sinks are used to keep computer chips in an acceptable temperature range. The heat sink base is 53 mm x 57 mm, and the maximum allowable chip temperature is 75 C. An array of 54 aluminum fins (k = 237 W/m*K) which have a square cross-section (3 mm x 3 mm) are attached to the heat sink. The length of each fin is 30 mm. The cooling air supplied to the heat sink is 25 C. If the convection heat transfer coefficient is 125 W/m2*K, what is the heat transfer rate (in W) from the heat sink, assuming adiabatic fin tips? (Hint: heat transfer does not solely occur from the fins.)