Questions from Principles Of Heat Transfer

Q: A long, 1-cm-diameter electric cable is embedded

A long, 1-cm-diameter electric cable is embedded in a concrete wall ( k 5 0.13 W/m K ) that is 1 m * 1 m, as shown in the sketch. If the lower surface is insulated, the surface of the cable is 100oC,...

Q: Determine the temperature distribution and heat flow rate per meter length in

Determine the temperature distribution and heat flow rate per meter length in a long concrete block having the shape shown below. The cross-sectional area of the block is square and the hole is center...

Q: A 30-cm-OD pipe with a surface temperature of

A 30-cm-OD pipe with a surface temperature of 90oC carries steam over a distance of 100 m. The pipe is buried with its centerline at a depth of 1 m, the ground surface is 26°C, and the mean...

Q: A plane wall of thickness 2L has internal heat sources whose strength

A plane wall of thickness 2L has internal heat sources whose strength varies according to where qo is the heat generated per unit volume at the center of the wall (x = 0) and a is a constant. If both...

Q: Two long pipes, one having a 10-cm OD and

Two long pipes, one having a 10-cm OD and a sur- face temperature of 300oC, the other having a 5-cm OD and a surface temperature of 100oC, are buried deeply in dry sand with their centerlines 15 cm ap...

Q: Using Table 1.4 as a guide, prepare a similar

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.

Q: A radioactive sample is to be stored in a protective box with

A radioactive sample is to be stored in a protective box with 4-cm-thick walls and interior dimensions of 4 cm * 4 cm * 12 cm. The radiation emitted by the sample is completely absorbed at the inner s...

Q: A 15-cm-OD pipe is buried with its centerline

A 15-cm-OD pipe is buried with its centerline 1.25 m below the surface of the ground (k of soil is 0.35 W/(m K)). An oil having a density of 800 kg/m3 and a specific heat of 2.1 kJ/(kg K) flows in the...

Q: A 2.5-cm-OD hot steam line at

A 2.5-cm-OD hot steam line at 100oC runs parallel to a 5.0-cm-OD cold water line at 15oC. The pipes are 5 cm apart (center to center) and deeply buried in concrete with a thermal conductivity of 0.87...

Q: Calculate the rate of heat transfer between a 15-cm-

Calculate the rate of heat transfer between a 15-cm- OD pipe at 1208C and a 10-cm-OD pipe at 408C. The two pipes are 330 m long and are buried in sand (k = 0.33 W/m K) 12 m below the surface (Ts = 25°...