Analysis And Design Of Ejector Refrigeration System

The energy shortage and environment problem along with human society progressare main obstacle in sustainable development. Clean and renewable energy, as a result,become the research focus. Ejector refrigeration cycle is proposed in this article as asolution. Mechanical energy is replaced by solar and waste enenrgy in this cycle, whichresults in better environment and energy efficiency improvement. However, ejector, as theheart of this noval refrigeration cycle, has a low performance which hinders its widespread.In this article exhaust gas from engine is employed as the heat source to powerejector refrigeration cycle. Based on the research of ejector optimal operating condition, amathematic design model is introduced to get the informantion of ejector’s sectiondimension. Experiment results are employed to verify the mathematic model. Then theejector characters are studied and factors which will influence the ejector performance isstudied, including: temperature difference, primary fluid superheat in heat exchanger,condsening temperature and subcool in condsenor, evaporating temperature and superheatin evaportor.Based on comparison among different refrigerants, R134a is selected in this design.Results from the design model are used in ejector section design. CFD analysis isempolyed to determine the nozzle exit position. The results show that1Dmix seems toobtain the best performance. Analysis model is intorduced in the following to study thedesigned ejector performance in all operating conditions. And solution is proposed whentha main ejector losses effectiveness in some extreme conditions.