Development of numerical modelling of isobutane vapour ejector.

Ejection system can be driven by free or inexpensive low temperature heat source, either solar or waste heat, as the main source of energy instead of electricity. These systems can be thought as a real alternative to compression devices in air-conditioning technologies. The paper deals with CFD numerical simulation along with experimental investigations carried out on a prototype for the case of isobutane as a working fluid under motive vapour temperature below 75°C. The numerical and experimental results of entrainment ratio were compared. A good accuracy between numerical and experimental results is observed. The divergent of the results are lower than 20% for tested series. The first results of LES (Large Eddy Simulation) modelling for isobutane vapour ejector are presented. The results show the actual state of the investigations.