A tube-launched rocket has stabilizing fins at its rear. During launch the fins experience hot gas at Tg = 1700 oC for a time t = 0.3 seconds. It is important that the fins survive launch without surface melting, T. Given the heat transfer coefficient is h, the heat flux per unit area is q=h(Tg-Ts). What is the objective for this design? High melting point Low thermal conductivity Launching efficiency Low melting point

A tube-launched rocket has stabilizing fins at its rear. During launch the fins experience hot gas at Tg = 1700 oC for a time t = 0.3 seconds. It is important that the fins survive launch without surface melting, T. Given the heat transfer coefficient is h, the heat flux per unit area is q=h(Tg-Ts). What is the objective for this design? High melting point Low thermal conductivity Launching efficiency Low melting point

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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1. A composite furnace wall is made up of a 12-in. lining of magnesite refractory brick, a 5-in.thickness of 85% magnesia, and a steel casing 0.10-in. thick. Flue gas temperature is 2200 F andthe boiler room is at 80 F. Gas side film coefficient is 15 Btu/hr-sq.ft-F and air side is 4.0.Determine:a. The thermal current Q/Ab. Interface temperaturesc. Effect on thermal current and inside refractory wall temperature if the magnesia insulation weredoubled.
sub-parts solved.
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Please include free body diagram and please don't type
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