A computer code has been developed for simulation of absorption systems in a flexible and modular form, which makes it possible to investigate various cycle configurations with different working fluids. The code is based on unit subroutines containing, the governing equations for the system’s components. Those are linked together by a main program according to the user’s specifications to form the complete system. The equations are solved simultaneously, and fluid properties are taken from a property database.

The code is user-oriented and requires a relatively simple input containing the given operating conditions and the working fluid at each state point. The user conveys to the computer an image of his cycle by specifying the different subunits and their interconnection. Based on this information, the program calculates the temperature, flow rate, concentration, pressure, and vapor fraction at each state point in the system and the heat duty at each unit, from which the coefficient of performance may be determined.

The program has been used successfully to simulate a variety of single-stage, double-stage, and dual-loop heat pumps and heat transformers, with the working fluids LiBr-H₂0, H₂0-NH₃, LiBr/H₂0-NH₃, LiBr/ZnBr₂-CH₃OH and more.

Units: Dual