Steam at 230°C is flowing through a steel pipe (k = 15W/m °C) whose inner and outer diameters are 90 mm and 100 mm, respectively, in an environment at 13°C. The pipe is insulated with 50-mm-thick fiberglass insulation (k 0.040W/m °C). If the heat transfer coefficients on the inside and the outside of the pipe are 5 and 0.9 W/m2 °C, respectively, determine the rate of heat loss from the steam per meter length of the pipe. What is the error involved in neglecting the thermal resistance of the steel pipe in calculations?

Steam at 230°C is flowing through a steel pipe (k = 15W/m °C) whose inner and outer diameters are 90 mm and 100 mm, respectively, in an environment at 13°C. The pipe is insulated with 50-mm-thick fiberglass insulation (k 0.040W/m °C). If the heat transfer coefficients on the inside and the outside of the pipe are 5 and 0.9 W/m2 °C, respectively, determine the rate of heat loss from the steam per meter length of the pipe. What is the error involved in neglecting the thermal resistance of the steel pipe in calculations?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

A 50-cm diameter pipeline in the Arctic carries hot oil where the outer surface is maintained at 30 °C and is exposed to a surrounding temperature of -17 °C. The convection heat-transfer coefficient on the outside of the pipe is 9 W/m2 °C. Estimate the energy loss from the pipe per meter of length.
In the effort to find the best way to cool a smooth thin-walled copper tube, an engineer decided to flow air either through the tube or across the outer tube surface. The tube has a diameter of 6 cm, and the surface temperature is maintained constant. Determine the convection heat transfer coefficient when air is flowing through a thin-walled tube at 25 m/s with bulk mean temperature of 50°C. _____ w/m^2k
To cool a storehouse in the summer without using a conventional air-conditioning system, the owner decided to hire an engineer to design an alternative system that would make use of the water in the nearby lake. The engineer decided to flow air through a thin smooth 10-cm-diameter copper tube that is submerged in the nearby lake. The water in the lake is typically maintained at a constant temperature of 15°C and a convection heat transfer coefficient of 1000 W/m2?K. If air (1 atm) enters the copper tube at a mean temperature of 30°C with an average velocity of 2.5 m/s, determine the necessary copper tube length so that the outlet mean temperature of the air is 20°C.
Estimate the natural convection heat transfer coefficient of the horizontal pipe. The outer surface temperature of the pipe is 80 ° C. The ambient air temperature is 40 ° C. The outer diameter of the pipe is 18 cm. Convection coefficient = Answer W / m² ° C.
What is the approximate temperature difference between a hot plate and the surrounding air if the heat flux from the plate is 800 W/m2? Assume that the air is flowing past the surface with a velocity of 5 m/s giving a heat transfer coefficient of 20 W/(m2K).
There are 3 windows in a room with a width of 100 cm and a height of 150 cm.There is a single glass (k=0. 9 W/mK) of 5 mm thickness in the windows initially. Instead of these glasses to save heatYou are considering replacing it with double glazing consisting of 5 mm glass and 12 mm air (k=0.022 W/mK). Indoor and outdoor environmenttemperatures are 20 0C and -10 0C, respectively, and the heat transfer coefficients are 7 W/m2 K and 25 W/m2 K. The total heat loss in the room is 3.5 kW.when switching to double glazing;a) Find the decrease in heat transfer. b) Considering that the heat given by the heaters remains 3.5 kW, what would the room temperature be?
....A journal bearing is to be used for a centrifugal pump where the shaft diameter is 50 mm and the bearing length is 80 mm. The ambient and bearing surface temperatures are 20°C and 45°C, respectively. Which of the following is the heat dissipated by the bearing if the heat dissipation coefficient is 280 W/m2-°C? Group of answer choices 56 W 14 W 73 W 28 W
The blades of a wind turbine turn a large shaft at a relatively slow speed. The rotational speed is increased by a gearbox that has an efficiency of 0.93. In turn, the gearbox output shaft drives an electric generator with an efficiency of 0.95. The cylindrical nacelle, which houses the gearbox, generator, and associated equipment, is of length L = 6 m and diameter D = 3 m. If the turbine produces P = 2.5 MW of electrical power, and the air and surroundings temperatures are T = 25 oC and Tsur = 20 oC, respectively, determine the minimum possible operating temperature inside the nacelle. The emissivity of the nacelle is 0.83, and the convective heat transfer coefficient is h = 35 W/m2 .K. The surface of the nacelle that is adjacent to the blade hub can be considered to be adiabatic, and solar irradiation may be neglected. Use Fin or N number of fins to reduce the Ts of the nacelle less than 143 oC
A steam pipe having a surface temperature of 200C passes through a room where thetemperature is 27C. the outside diameter of pipe is 80mm and emissivity factor is 0.8. Calculatethe radiated heat loss for 3 m pipe length.
Estimate the natural convection heat transfer coefficient of the horizontal pipe. The temperature of the outer surface of the pipe is 120 ° C. The ambient air temperature is 40 ° C. The outer diameter of the pipe is 18 cm. Convection coefficient = ..... W / m² ° C.
Clothing made of several thin layers of fabric with trapped air in between, often called ski clothing, is commonly used in cold climates because it is light, fashionable, and a very effective thermal insulator. So it is no surprise that such clothing has largely replaced thick and heavy old-fashioned coats. Consider a jacket made of five layers of 0.1-mm-thick synthetic fabric (k = 0.13 W/m·K) with 1.5-mm-thick air space (k = 0.026 W/m·K) between the layers. Assuming the inner surface temperature of the jacket to be 28°C and the surface area to be 1.25 m2, determine the rate of heat loss through the jacket when the temperature of the outdoors is 0°C and the heat transfer coefficient at the outer surface is 25 W/m2·K. What would your response be if the jacket is made of a single layer of 0.5-mm-thick synthetic fabric? What should be the thickness of a wool fabric (k = 0.035 W/m·K) if the person is to achieve the same level of thermal comfort wearing a thick wool coat instead of a…
The walls of the refrigerated storage room are 10 m long and 3 m high and constructed with 90 mm concrete blocks (k = 0.935 W / [m ° C]) and 12 cm fiber insulation board (k = 0.048 W). / [m ° C]). The temperature of the cold room is -10 ° C and the convective hot coupling is 40 W / (m² K); The outside air temperature is 30 ° C with a convection heat transfer coefficient of 10 W / (m² K). Calculate the total heat wave. Total heat transfer coefficient = Answer W / (m² K).