Page 84 - Entrophy Analysis in Thermal Engineering Systems

76 Entropy Analysis in Thermal Engineering Systems

Fig. 6.6 Variation of the thermal efficiency, normalized power output, and normalized
entropy production rate at r T ¼ 6 (A) Novikov’ engine, and (B) modified Novikov’s
engine.

∗
the normalized entropy production rate Φ are defined the same way as
before. However, because K l !∞ for the case of the modified Novikov’s

∗
engine (Fig. 6.6B), these two parameters are defined as W ∗ ¼ _ W =K h T L
and Φ ¼Φ/K h . Also, note that the results for the Novikov’s model are pres-
ented as a function of T EH /T L , whereas those for the modified Novikov’s
model are depicted versus T EL /T L .
Fig. 6.6 reveals that an increase in the entropy production is equivalent to
a decrease in the thermal efficiency in both Novikov’s and modified