Natural gas (methane) is to be transported in a 20-in. id pipeline over level terrain. each pumping station increases the pressure to 100 psia and the pressure drops to 25 psia at the inlet to the next pumping station located 50 miles away. what is the gas flow rate in cubic feet per hour measured at 60°f and 30 in. mm hg pressure?

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.