Numeric simulation of an integrated CO 2 cooling system

In a research project of EADS Airbus and the TUHH a system simulation of a cooling system is to be realized, using the refrigerant carbondioxid (CO2). The simulation models of the cooling cycle are created using Modelica and the thermohydraulic model library ThermoFlow. Modelica and the model library operate since spring 2000. The project will be finished untill the end of 2002. For the structure of the CO2 models so far a FORTRAN program was introduced in Modelica that calculates the state variables of CO2 using an equation of state. Furthermore the heat transfer and pressure loss relations were implemented of CO2 for oneand two-phase and the supercritical status area. Literature reviews of currently measured results were used to check the models. Therefore, the modelling of pipes, evaporators and gascooler/condenser is possible. First results of an uncomplex CO2 -refrigertion cycle are presented and a preview of future work is given.