Optimum Refrigerant Selection for Low Temperature Engineering

Abstract

The selection of refrigerants or refrigerant mixtures with desirable combination of such properties as contribution to greenhouse effect, flammability, toxicity, thermodynamic behavior, performance specifications, and the others is one of the most important stages in simulation and design of refrigeration processes. Refrigerant selection problem has been tackled using achievements of molecular theory, engineering experience and experimental studies [1], [2], [3], [4], [5], [6]. The identification of the structural formulas of a substances along with the synthesis of new substances having desirable properties is carried out most intensively by applying computer aided molecular design. This approach is an inverse engineering problem of incorporating property and technological performances directly into the design of the desired refrigerant. Clearly, a refrigerant that combines all the desirable properties and has no undesirable properties does not exist. However, algorithms for searching of a “tailored” refrigerant with desirable combination of properties are able to formulate mathematically on the basis of the multi-criteria decision making approach. It is evident that the task of an optimum refrigerant selection, being complex by nature, requires the system’s analysis tools for these purposes. A synergetic combination of theoretical and restricted experimental studies seems an optimum way to selection of necessary working fluid for lowtemperature engineering applications.