In the figure above, a closed thermodynamic cycle, known as the Stirling Cycle,
ID: 1489612 • Letter: I
Question
In the figure above, a closed thermodynamic cycle, known as the Stirling Cycle, is shown. It consists of four processes using a diatomic ideal gas: a) The gas expands at a constant temperature, TH=350 K, from V1 to V2, b) The gas is cooled at constant volume, V2, from TH to TC=270 K, c) The gas is compressed at constant temperature, TC, from volume V2 to V1, d) The gas is heated at constant volume, V1, back to the initial state. Assume that V2 = 2.0 V1 and there are 0.7 moles of gas. What is the total heat exchanged with the environment, Q, for one entire cycle of the engine? (Your answer should be in Joules but don't include the units in your answer.)
T=Explanation / Answer
for the process at temperature TH ,the heat is taken fron the environment
heat taken = work done in isothermal process=nRTHln(V2/V1)=nRTHln(2)
for the process at temperature TC.the heat is given back to environment
heat given=work done in isohermal process=nRTCln(V2/V1)=nRTCln(2)
for the two isobaric process heat will cancel out as there is same temperature change in both.
net heat exchange =nRTHln(2)-nRTCln(2)=nRln(2)(TH-TC)=0.7*8.314ln(2)(350-270)=322.72