Refrigerant 134a enters the condenser of a residential heat pump at 800 kPa and 55 oC at a rate of 0.018 kg/s and leaves at 750 kPa and saturated liquid condition. The refrigerant enters the compressor at 200 kPa superheated by 5 oC. Determine a) the isentropic efficiency of the compressor, b) the rate of heat supplied to the room and c) the COP of the heat pump.

Explain the difference laminar and turbulent flow. explain it with the shear stress and the velocity profiles.

Derive the correction factor formula for conical nozzle i=-(1+ cosa) and calculate the nozzle angle correction factor for a nozzle whose divergence hal-fangle is 13 (hint: assume that all the mass flow originates at the apex of the cone.

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.