Consider an ideal gas-turbine cycle with two stages of compression and two stages of expansion. the pressure ratio across each stage of the compressor and turbine is 3. the air enters each stage of the compressor at 300 k and each stage of the turbine at 1200 k. determine the back work ratio and the thermal efficiency of the cycle, assuming (a) no regenerator is used and (b) a regenerator with 75 percent effectiveness is used. use variable specific heats.

Amass of m 1.5 kg of steam is contained in a closed rigid container. initially the pressure and temperature of the steam are: p 1.5 mpa and t 240°c (superheated state), respectively. then the temperature drops to t2= 100°c as the result of heat transfer to the surroundings. determine: a) quality of the steam at the end of the process, b) heat transfer with the surroundings. for: p1.5 mpa and t 240°c: enthalpy of superheated vapour is 2900 kj/kg, specific volume of superheated vapour is 0. 1483 m/kg, while for t 100°c: enthalpy of saturated liquid water is 419kj/kg, specific volume of saturated liquid water is 0.001043m/kg, enthalpy of saturated vapour is 2676 kj/kg, specific volume of saturated vapour is 1.672 m/kg and pressure is 0.1 mpa.

Calculate the bore of a cylinder that has a stroke of 18 inches and an extension time of 6 seconds at a flow rate of 4 gal/min.

Select any two (2) areas of applications of chain-drive. (clo4) a)-permanent lubrication necessary b)-hydraulic forklift truck operation c)-rigging and heavy moving materials d)-relatively high maintenance costs e)-costlier than belt drives