Study of Plate Type Ejector Refrigerating Syatem

• Main Authors: Pin-LingHsu, 許丙霖
• Other Authors: Jung-Hua Chou
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/6b87vz

碩士 === 國立成功大學 === 工程科學系 === 102 === In order to establish a generalizable small-capacity ejector refrigerating system, this study aims at optimizing the entrainment rate of the system by re-designing and fabricating the core ejector. The process of designing an optimized core ejector has been constructed, and the design verification test was also employed. The design processes are as follows. First, construct a simulation model by CFD. Second, use the ejector principle and choke effect to validate the model. Third, design a nozzle throat, a nozzle exit, and cross-sectional area via the one-dimension ejector theory. Furthermore, the Taguchi method (L9 orthogonal array) and two dimensional numerical simulations were employed to optimize the length and angle. Finally, verify the gas entrainment rate under different pressure and temperature settings. In the pilot run, I used two acrylic sheets to fabricate an ejector, and selected Novec 649 as the working fluid. Through the Taguchi designing process, the suction efficiency of the analog part was increased by 16.2%, and the interaction was increased by 4.7%, while the designing process can be the basis of establishing plate type ejectors. In the verification section, the data can not be effectively verified because the pressure vessels cannot maintain a stable pressure for sufficient time; therefore, the measured data is in transient form, which can only prove the suction effect.