Air is entering a 4200-kw turbine that is operating at its steady state. the mass flow rate is 20 kg/s at 807 c, 5 bar and a velocity of 100 m/s. this air then expands adiabatically, through the turbine and exits at a velocity of 125 m/s. afterwards the air then enters a diffuser where it decelerates isentropically to a velocity of 15 m/s and a pressure of 1 bar. using the ideal gas model, determine, (a) pressure and temperature of the air at the turbine exit, in units of bar and kelvin. (b) entropy production rate in the turbine in units of kw/k, and (c) draw the process on a t-s diagram.

Acompressor receives the shaft work to decrease the pressure of the fluid. 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?

Manometers are good examples of measuring instruments, nowadays they are not as common as before. a)-capacitive probe gauges b)-gravitational gauges deformation ) gauges d)-digital gauges