An air compressor takes in atmospheric air and compresses it to a pressure of 150 psig. Th e air temperature increases to 135°F, which is too warm to use for most industrial applications. Th e warmed...

An air compressor takes in atmospheric air and compresses it to a pressure of 150 psig. Th e air temperature increases to 135°F, which is too warm to use for most industrial applications. Th e warmed compressed air is channeled to a double-pipe heat exchanger (called an intercooler), where water circulates through the annulus. Th e water-fl ow rate is very high, and the wall of the tube carrying the air is kept roughly at a constant temperature of 65°F. Th e intercooler is to cool the air to 75°F. How long an intercooler is necessary if the mass fl ow of air is 5 lbm/hr and the tube is 5/8 standard type K copper? What is the air pressure at the end of the intercooler?