Two reversible power cycles are arranged in series. thefirst
cycle recieves energy by heat transfer from a hot reservoirat
temperature th, and rejects energy by heat transfer to areservoir
at an intermediate temperature t < th. thesecond cycle recieves
energy by heat transfer from the reservoir attemperature t and
rejects energy by heat transfer to a coldreservoir at temperature
tc < t.
a) obtain an expression for the thermal efficiency of a
singlereversible power cycle operating between hot and cold
reservoirs atth and tc, respectively, in terms of the thermal
efficiencies ofthe two cycles.
b) obtain an expression for the intermediate temperature t
interms of th and tc for the special case where the
thermalefficiencies are equal.