Steels of various grades are often heat treated to achieve particular properties,dependent on application. However, process heating accounts for a considerableamount of all energy use in the manufacturing sector (~35%--insane!). Therefore, it isdesirable from a financial standpoint to minimize heat treatment duration while stillobtaining the desired properties.Consider a steel (K = 40.0 W/mk, P = 7940 k8 /m3 , Cp = 435J/kg-k) shaft of%Ddiameter 90 mm which is to be heat treated in a gas-fired furnace. The gases insidethe furnace are at a steady T = 1300 K, and the heat transfer coefficient ofconvection is h = 70 W/m².k. If the shaft is at 310 K when it enters the furnace,estimate how long it must remain in the furnace to obtain a centerline temperatureof 700 K, in minutes.

Answered: Image /qna-images/answer/401171ee-9da4-40cd-aa85-d45563d07887.jpg

Consider a steel (K = 40.0 W/mk, P = 7940 k8 /m? , Cp = 435J/kg-k) shaft of %3D diameter 90 mm which is to be heat treated in a gas-fired furnace. The gases inside the furnace are at a steady T = 1300 K, and the heat transfer coefficient of convection is h = 70 W/m²k. If the shaft is at 310 K when it enters the furnace, %D estimate how long it must remain in the furnace to obtain a centerline temperature of 700 K, in minutes.

Consider a steel (K = 40.0 W/mk, P = 7940 k8 /m? , Cp = 435J/kg-k) shaft of %3D diameter 90 mm which is to be heat treated in a gas-fired furnace. The gases inside the furnace are at a steady T = 1300 K, and the heat transfer coefficient of convection is h = 70 W/m²k. If the shaft is at 310 K when it enters the furnace, %D estimate how long it must remain in the furnace to obtain a centerline temperature of 700 K, in minutes.

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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