TR2012-056

Fast Refrigerant Property Calculations Using Interpolation-Based Methods



TR Image

An interpolation-based method for computing refrigerant properties which can be used in simulations of vapor-compression air-conditioning equipment is presented. This method uses bicubic functions to interpolate between samples of the Helmholtz energy surface as a function of temperature and density. Three beneficial characteristics of this method are discussed: speed, accuracy, and consistency, as well as a means for using a variety of different independent variables are also presented. The implementation of this method is discussed, and experimental results for property calculations for refrigerant R-134a are presented which compare favorably to standard Newton-based equation of state methods.