Halliday says that the efficiency of an ideal Stirling engine is lower than that of a ideal Carnot engine?? But why??(adsbygoogle = window.adsbygoogle || []).push({});

It seems to me that there efficiency are both [tex] \epsilon =1-\frac{T_L}{T_H} [/tex]

Though Halldiay also say that this equation do not apply to Stirning engine but only to Carnot

Though Stirling engine involves two isochoric process, so unlike carnot which the two isothermal process are connected by adiabatic process, the entropy do change between the two temperature in the Stirling Cycle.

But from [tex] \Delta S = nR ln \frac{V_f}{V_i} + nC_V ln \frac{T_f}{T_i} [/tex]

we can know that the entropy change in the two isochoric process of Stirling cycle canceled out. and still

[tex] \frac{|Q_H|}{T_H} = \frac{|Q_L}{T_H} [/tex] just like Carnot Cycle

So I think efficiency [tex] \epsilon=1-\frac{T_L}{T_H} [/tex] can apply to Stirling

Am I wrong??

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Carnot and Stirling engine

**Physics Forums | Science Articles, Homework Help, Discussion**