A Thomas meter is located in an air duct of 2 sq ft cross-sectional area. The air weighs 0.083 lb per cu ft, and its specific heat is 0.24. Assume a controlled temperature differential of 5° and heater potential of 110 volts. Plot the velocity as abscissa and amperage as ordinate for veloc- ity 0 to 300 ft per min. Assume constant amperage of 3, and plot tem- perature difference against velocity. Discuss the curves from the stand- point of accuracy of the system.

A Thomas meter is located in an air duct of 2 sq ft cross-sectional area. The air weighs 0.083 lb per cu ft, and its specific heat is 0.24. Assume a controlled temperature differential of 5° and heater potential of 110 volts. Plot the velocity as abscissa and amperage as ordinate for veloc- ity 0 to 300 ft per min. Assume constant amperage of 3, and plot tem- perature difference against velocity. Discuss the curves from the stand- point of accuracy of the system.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter10: Heat Exchangers

Section: Chapter Questions

Problem 10.19P

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