Suppose an engineer suggests that air is to be used instead of water in the tube of

Question:

Suppose an engineer suggests that air is to be used instead of water in the tube of Problem 6.24 and the velocity of the air is to be increased until the heat transfer coefficient with the air equals that obtained with water at 1.5 m/s. Determine the velocity required and comment on the feasibility of the engineer??s suggestion. Note that the speed of sound in air at 100?C is 387 m/s. From Problem 6.24: Water at a bulk inlet temperature of 93?C is flowing with a velocity of 1.5 m/s through a 0.015-m-diameter tube, 0.3 m long. If the tube wall temperature is 204?C, determine the average heat transfer coefficient and estimate the bulk temperature rise of the water.GIVENAir flow through a tubeBulk inlet air temperature (Tb,in) = 93?CTube diameter (D) = 0.015 mTube length (L) = 0.3 mTube surface temperature (Ts) = 204?CFrom Problem 6.23: hc,L = 13,037 W/(m2 K)ASSUMPTIONSSteady stateConstant and uniform tubetemperature