AN ANALYTICAL FORMULA FOR THE ESTIMATION OF A RANKINE-CYCLE HEAT ENGINE EFFICIENCY AT MAXIMUM POWER

Abstract

The authors develop an analytical formula for estimating the Rankine power cycle efficiency at maximum power, which can be extracted from the given mass flow rates of heating and cooling fluids. This formula does not need any detailed thermodynamic data. The accuracy of the procedure is shown by comparisons between analytical values and those calculated using detailed thermodynamic data. The results indicate that the thermal efficiency at maximum power depends primarily on the initial temperatures of the heating and cooling fluids and pinch-temperature differences between the working fluid and the heating and cooling fluids. The efficiency at maximum power provides a measure of the power available in a Rankine heat engine.