H = KA(T2 - T1)/x
H = 427*(3.14*0.0303^2/4)(6)/0.43
H = 4.5 W
For solid silver Q = 4.5 J
Qgiven = 3543 J
Qgiven/Q = 3543/4.5 = 787.3
A pipe 0.0303 m in diameter and 0.43 m long can transfer 3543 J of heat...
6 Water is heated in a pipe by exchanging heat with a warmer fluid that flows outside the pipe. Inside diameter of the pipe is dn 0.045 m and outside diameter dour0.05 m. Mean velocity of the water in the pipe is um-0.31 m/s and the bulk temperature is 323 K (density 988 kg m-3; viscosity 0.00055 kg m' sı. Pr 3.56, thermal conductivity k 0.64 W m1 Kt). The material of the pipe has thermal conductivity k 0.61 W...
DON’T disregard the thermal conductivity of the pipe
3.) Oil at 200 C flows in a pipeline. The pipe has a 30-cm diameter and the flow is at an average velocity of 2 m/s. A 200-m-long section of the pipeline passes through icy waters of a lake at 0° C. The pipe is uncoated carbon steel with a thermal conductivity of 61 W/m o C. Determine (a) the temperature of the oil when the pipe leaves the lake, (b) the...
HEAT TRANSFER 2. A steam pipe, 12 m in length and 10 cm in diameter, is exposed to the cross flow of air at 5°C with the velocity of 25 km/h. The surface of the pipe is maintained at 75°C and its emissivity is estimated to be 0.8. The surrounding temperature is at 0°C. Determined the total heat loss from the pipe.
4. (25 pts) Water is flowing inside a thin wall, smooth pipe of diameter 0.05 m at a mass flowrate of 0.3 kg/s. The water enters the pipe at a mean temperature Tm,i= 80 °C and exits at Tm,o= 80 °C while the pipe surface temperature is maintained at Ts= 20 °C along its entire length. a. Is the flow turbulent or laminar? b. Calculate the average convection heat transfer coefficient inside the tube. c. Calculate the length of the...
Exercise 1.16 An insulated district heating pipe with a total diameter d = 0.4 m is laid in the ground at a depth of h = 1.2 m. For a long cold period with an average ground surface temperature of 0°C and a temperature at the outer edge of the pipe insulation of 20°C, the heat loss per 1km of steam pipe must be calculated. The thermal conductivity of the soil should be assumed to be 0.6 W/mk
Exercise 1.16...
Problem 1. Steam at 120°C is transported in a long 8" outer diameter pipe. Its outer surface is covered with a 1" thick fiberglass (thermal conductivity, 0.05 W/(mK)) insulation. When the outer temperature is 0°C, the rate of condensation of steam is measured to equal 0.06 g per meter of the pipe length. Estimate the heat transfer coefficient. The heat of vaporization of the steam is 2600 J/g. The resistance to the heat transfer through the pipe wall may be...
Problem 2 (10/30) - Steam at 180 C (saturated) enters a 10 cm diameter, 0.4 mm thick, 150 m long carbon steel pipe which is exposed to the elements. Air flows across the pipe at 10 m/sec. Air emperature is 20 C. Convective heat transfer of stem to the pipe is very high. Emissivity of the pipe is estimated at 0.8.Calculate the rate of heat transfer from the pipe. State any assumptions.
Problem 2 (10/30) - Steam at 180 C...
PLEASE ANSWER a,b,c
Heat Conduction Heat conduction occurs through any material, represented here by a rectangular bar, whether window glass or walrus blubber. The temperature of the material is T2 on the left and T1 on the right, where T2 is greater than T1. The rate of heat transfer by conduction is directly proportional to the surface area A, the temperature difference T2 - T1, and the substance's conductivity k. The rate of heat transfer is inversely proportional to the...
heat and mass transfer
(20 points) Air at 25°C cools a 2170 cylindrical battery (with a diameter of 21 mm and a length of 70 mm) with a cross flow velocity of 6 m/s. a) Determine the average convective heat transfer coefficient. (b) If the battery's internal heat generation is 5W and its thermal conductivity is 0.6 w/m-k, the determine the battery surface temperature and the maximum temperature in battery
(20 points) Air at 25°C cools a 2170 cylindrical battery...
Problem 3 (30): Steam at Too,1 340 °C flows in a cast iron pipe [k- 80 W/m.°C] whose inner and outer diameter are Di 6 cm and D2 -8 cm, respectively. The pipe is covered with a 4-cm thick glass wool insulation [k-0.05 W/ m°C]. Heat is lost to the surroundings at Too,2 - 21°C by natural convection and radiation, with a combined heat transfer coefficient of h- 18 W/m2 °C. Taking the heat transfer coefficient inside the pipe to...