Refrigerant 134a is the working fluid in an ideal vapor-compression refrigeration cycle that communicates thermally with a cold region at -8 degree C and a warm region at 30 degree C. Saturated vapor enters the compressor at -8 degree C and saturated liquid leaves the condenser at 30 degree C. The mass flow rate of the refrigerant is 0.08 kg/s. Determine (a) the compressor power, in kW (20 points) (b) the refrigeration capacity, in tons (20 points) (c) the coefficient of performance (10 points)

Asingle-geared blanking press has a stroke of 200 mm and a rated capacity of 320 kn. a cam driven ram is assumed to be capable of delivering the full press load at constant force during the last 15 percent of a constant-velocity stroke. the camshaft has an average speed of 90 rev/min and is geared to the flywheel shaft at a 6: 1 ratio. the total work done is to include an allowance of 16 percent for friction a) estimate the maximum energy fluctuation b) find the rim weight for an effective diameter of 1.2 m and a coefficient of speed fluctuation of 0.10

Determine whether or not it is possible to compress air adiabatically from k to 140 kpa and 400 k. what is the entropy change during this process?

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.