基于传热窄点的非共沸混合工质优选方法

为了解决多种非共沸工质的优选问题,提出了一种基于传热窄点的分析方法．应用CSD状态方程得到不 同非共沸工质相变时焓差随相变温度的变化规律,并在适当假设的基础上,再得到换热流体的温度分布,从而得到 不同非共沸工质的相变传热窄点位置和大小,结合统计学方法,尝试给出了一种非共沸混合工质的优选方法．针对 两种非共沸工质(R401A和R409A)应用了两种不同的比较方法,比较结果均为R401A优于R409A,但新方法更加 简便．

Zeotropic Mixture Selection Based on Heat Transfer Pinch Point

This paper proposes a method, which is based on heat transfer pinch point, for the selection of zeo-tropic mixtures to be used in the same work condition. In the research the CSD situation equation was adopted to identify the rule according to which the enthalpy of the zeotropic mixture changed with the variation of its temperature when its phase changing happened. Based on hypotheses, temperature distribution of heat-transfer fluids were obtained. In addition, the positions and the value of heat transfer pinch points of different mixtures were obtained. Based on statistical theory, a novel optimal selection method is proposed. Two methods were a dopted to evaluate two mixtures, R401A and R409A. The research concludes that R401A is better than R409A, but the novel method is easier than the other one.