Steam enters a counterflow heat exchanger operating at steady state at 0.05 mpa with a quality of 0.9 and exits at the same pressure as saturated liquid. the steam mass flow rate is 1.3 kg/min. a separate stream of air with a mass flow rate of 100 kg/min enters at 30oc and exits at 60°c. the ideal gas model with cp = 1.005 kj/kg·k can be assumed for air. kinetic and potential energy effects are negligible. determine the temperature of the entering steam, in °c. for the overall heat exchanger as the control volume, what is the rate of heat transfer, in kw.

The temperature of air decreases as it is compressed by an adiabatic compressor. a)- true b)- false

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?

Give heat transfer applications for the following, (i) gas turbines (propulsion) ) gas turbines (power generation). (iii) steam turbines. (iv) combined heat and power (chp). (v) automotive engines