1. A furnace is of cubical shape with the dimensions of 4m X 4m X 4m. The top surface isheated by electric resistance heaters providing a power input of3.5x10 W, the side wallsare well insulated, and the bottom surface is maintained at 350K. Calculate thetemperatures of the top and side surfaces if the emissivities of the top and bottom surfacesare 0.7 and 0.5, respectively.

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A furnace is of cubical shape with the dimensions of 4m X 4m X 4m. The top surfac ted by electric resistance heaters providing a power input of 3.5x10 W, the side w well insulated, and the bottom surface is maintained at 350K. Calculate peratures of the top and side surfaces if the emissivities of the top and bottom surfa

A furnace is of cubical shape with the dimensions of 4m X 4m X 4m. The top surfac ted by electric resistance heaters providing a power input of 3.5x10 W, the side w well insulated, and the bottom surface is maintained at 350K. Calculate peratures of the top and side surfaces if the emissivities of the top and bottom surfa

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

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MATLAB PROBLEM
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A manufacturing facility located at 32° N latitude has a glazing area of 60 m² facing west that consists of double pane windows made of clear glass (SHGC = 0.766). To reduce the solar heat gain in summer, a reflective film that will reduce the SHGC to 0.35 is considered. The cooling season consists of June, July, August, and September, and the heating season, October through April. The average daily solar heat fluxes incident on the west side at this latitude are 2.35, 3.03, 3.62, 4.00, 4.20, 4.24, 4.16, 3.93, 3.48, 2.94, 2.33, and 2.07 kWh/day · m² for January through December, respectively. Also, the unit costs of electricity and natural gas are $0.09/kWh and $0.45/therm., respectively. If the coefficient of performance of the cooling system is 3.2 and the efficiency of the furnace is 0.90, determine the net annual cost savings due to installing reflective coating on the windows. Also, determine the simple payback period if the installation cost of reflective film is $20/m². Answers:…
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A blackbody of surface area 10 cm' is heated to 127°C and is suspended in a room at temperature 27°C. Calculate the initial rate of loss of heat fron the body to the room.
A long, horizontal, cylindrical steel reactor, 1 m in diameter, has a surface temperature of 300ºC. The emissivity of the steel is 0.6, and the heat transfer coefficient for natural convection is 5 W m−2 K−1 . Heat is lost by convection to the air at 15ºC, and also by radiation to the surroundings, which can be considered to be a black body at 15ºC. a) Calculate the total heat loss per metre length of the reactor, and the proportions lost by convection and radiation b) The reactor is then insulated with a thin layer of insulation material to reduce the total heat loss to one-tenth of its original value. This causes the surface temperature of the steel to rise to 400ºC. The thermal conductivity of the insulation is 0.01 W m−1 K−1 , and its surface emissivity is 0.2. Show that the resulting surface temperature of the insulation is about 89ºC, and calculate the thickness of insulation required, stating any assumptions made. Specifically need help with part b
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