Consider a 0.8-m-high and 1.5-m-wide glass window with a thickness of 8 mm and a thermal conductivity of 0.78 W/m-K. Determine the steady rate of heat transfer through this glass window and the temperature of its inner surface for a day during which the room is maintained at 29°C while the temperature of the outdoors is -12°C. Take the heat transfer coefficients on the inner surface of the window to be h1 = 15 W/m2-K and outer surfaces of the window to be h, = 40 W/m2-K, which includes the effects of radiation. Answer shows Qtotal and Temperature at inner surface of window. 412W, 0.1°C a. 483W, 2.2°C b. 424W, 0.5°C 436W, 0.8°C d. 459W, 1.5°C е.

Consider a 0.8-m-high and 1.5-m-wide glass window with a thickness of 8 mm and a thermal conductivity of 0.78 W/m-K. Determine the steady rate of heat transfer through this glass window and the temperature of its inner surface for a day during which the room is maintained at 29°C while the temperature of the outdoors is -12°C. Take the heat transfer coefficients on the inner surface of the window to be h1 = 15 W/m2-K and outer surfaces of the window to be h, = 40 W/m2-K, which includes the effects of radiation. Answer shows Qtotal and Temperature at inner surface of window. 412W, 0.1°C a. 483W, 2.2°C b. 424W, 0.5°C 436W, 0.8°C d. 459W, 1.5°C е.

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 wall with a brick and concrete layer is shown in the figure. The wall has a length of 15 m and 6 m high. The brick (k = 1.3 W/m-K) has a thickness of 75 mm and the concrete (k = 2 W/m-K) is 150 mm thick. Determine the total heat resistance, the heat transfer rate through the wall, and the temperature of its inner surface for a day during which the room is maintained at 20°C while the temperature of the outdoors is 32°C. Take the convection heat transfer coefficients on the inner and outer surfaces of the wall to be 12 W/m²-K and 18 W/m²-K, respectively, which includes the effects of radiation. Round off your final answer to three (3) decimal places. (20 pts.) Tooout Outdoor Brick Concrete Wall Heat Transfer, Q (W) = Total Heat Resistance, RT (K/W) = input: 2.01234x10^-3) T₂ Inner Surface Temp, T2 (°C) = Toin Indoor (5 decimal places - example
Determine the heat flow (in Watts) across a plane wall of 8.1m thickness with a constant thermal conductivity of 9.67 W/mK when the surface temperatures are steady at 422°C and 73.5°C. The wall area is 29m². Reduce your answer into two decimal places. T, -L-
Consider a person standing in a room kept at 22°C at all times. Your house It has been observed that the inner surfaces of the walls, floor and ceiling are at an average temperature of 15°C. If this person's exposed surface area is 1.4 m2 and if the average external surface temperature is 30°C, this person and the surrounding surfaces Determine the radiation and heat transfer rate between One's emissivity, the Stefan-Boltzmann constant a=5,67x10 -8 W/m 2 K 4
A wall with a brick and concrete layer is shown in the figure. The wall has a length of 15 m and 6 m high. The brick (k = 1.3 W/m-K) has a thickness of 75 mm and the concrete (k = 2 W/m-K) is 150 mm thick. Determine the total heat resistance, the heat transfer rate through the wall, and the temperature of its inner surface for a day during which the room is maintained at 20°C while the temperature of the outdoors is 32°C. Take the convection heat transfer coefficients on the inner and outer surfaces of the wall to be 12 W/m2-K and 18 W/m2-K, respectively, which includes the effects of radiation. Round off your final answer to three (3) decimal places.
Consider a person standing in a room at 18°C. Determine the total rate of heat transfer from this person if the exposed surface area and the skin temperature of the person are 1.7 m2 and 32°C. respectively, and the convection heat transfer coefficient is 5 W/m2-K. Take the emissivity of the skin and the clothes to be 0.9, and assume the temperature of the inner surfaces of the room to be the same as the air temperature.
The wall of an oven in an industrial plant, made of fire brick (k = 0.71 W/m/K) has thickness of L = 15 cm. The oven is exposed to air at 28oC and the surfaces of the far surroundings are at 20oC. If the temperature of the outer surface of the wall is 92oC and the heat transfer coefficient and emissivity are 20 W/(m^2*K) and 0.8 respectively, determine the temperature of the inner surface of the wall.
An electrical wire with 0.4cm in diameter and 2.5m long extends across a room with 15deg C temperature. Heat is generated in the wire as a result of resistance heating, and the surface of the wire is measured to be 162degC. the voltage drop and electric current along the wire is 60V and 1.64 A, respectively. Determine the convection heat transfer coefficient for the heat transfer between the surface of the wire and the room air. Hint, electric power formula. Round your answer to 2 decimal places.
None
Citrus fruits are very susceptible to cold weather, and extended exposure to subfreezing temperatures can destroy them. Consider an 8-cm-diameter orange that is initially at 15°C. A cold front moves in one night, and the ambient temperature suddenly drops to –6°C, with a heat transfer coefficient of 15 W/m2·K. Using the properties of water for the orange and assuming the ambient conditions to remain constant for 20400 seconds before the cold front moves out, determine the surface temperature of orange that night. Solve this problem using analytical one-term approximation method. The properties of the orange are approximated by those of water at the average temperature of about 5°C, k = 0.571 W/m·°C and α = 0.136 × 10–6 m2/s. The surface temperature of orange that night is
An electric device made of copper stands on an insulating carpet in a breezy room at 20°C. A fan is set in the room to ensure a continuous air circulation. Determine the total rate of heat transfer from the device if the average values of its exposed surface area and outer surface temperature are 2.5 m² and 30°C, respectively.