Increasing the efficiency of power plants with heat recovery of automotive equipment by using a working substance with optimal physical properties

An urgent issue is to increase the efficiency of the internal combustion engine through the use of a Rankine regenerative cycle, which allows converting heat losses into additional useful work, which can lead to lower fuel consumption and resource savings.

Based on the analysis of modern literature, it has been shown that the effectiveness of the Rankine cycle depends on the properties of the working substances that implement the cycle. The paper examines the effects of the physical properties of working substances on the efficiency of the Rankine regenerative cycle. At the same time, all working substances are divided into three groups: 1–3 atomic, 4–6 atomic and with more than six atoms. Each group has its own type of T-S chart. Physical and mathematical models of physical properties have been developed for each group of substances.

Based on models of physical properties, expressions for the efficiency of the Rankine cycle for these groups of substances are obtained. Moreover, dimensionless relative and reduced values are introduced into consideration. The author provides a numerical and graphical analysis of the dependence of the efficiency of the Rankine cycle on the basic dimensionless quantities. Therefore, the author develops recommendations for the selection or synthesis of the optimal working substance implementing the Rankine cycle.

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