if a steam engine has an inlet of 280 degrees C and an outlet of 28 degrees C, and the efficiency of this engine is 55%, calculate the heat discarded by the engine if the entropy change of the system during isothermal expansion is 840JK^-1.

It is planned to build a geothermal power plant for electricity generation purposes. The subsoil water reaches temperatures close to 170 ° C while the ambient temperature is 20 ° C. Find the maximum efficiency that a geothermal plant could aspire to if installed in that location.   Ans: η=33.85%

Ao air turbine with one intet and one exit operates at Steady State, and has heat trans fer to the Surroundings at an average 3.0x' 10" J per ka of air flowing. The inlet conditions are 980°K and 400 kPa, and the exit conditions are 670°k and 100 kla. Neglect kinetic and potential energy e ffects and use the ideal gas madel without assumung constant specific heats, to calculate the entropy producHon per mass of air flowing. Pres ent your answer in kJ/ (kgʻk) wsing 5 Signifigant figures. outer surface temperature of 315°k ät the rate of

GRAPH TO SCALEair compression process from 1 bar and 0.88m3/kg up to 6 bar.Take the compression function to be:A:pv=cteB:pv^1.4=cteC:pv^1.2=cte