Engineering, 28.09.2019 00:30, cameronbeaugh

Apipe heater (long cylinder shape 30 mm outside diameter) is inserted through the side of a pipe in which water or air is flowing. the heater is perpendicular to fluid flow. when water with a temperature of 25°c and velocity of 1 m/s flows in the pipe over the heater, the power per unit length of the heater delivered to maintain the heater outer surface at a uniform temperature of 90°c is 28 kw/m length. when air, also at 25°c, but with a velocity of 10 m/s is flowing, the power per unit length to maintain the same surface temperature is 400 w/m. calculate and discuss comparisons between the convection coefficients for the flows of water and air. assume all of the power provided to the heater is given off as heat to the air or water.

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Apipe heater (long cylinder shape 30 mm outside diameter) is inserted through the side of a pipe in...