Feng Jianmei,Qu Zongchang,Li Xinwei
(School of Energy and Power Engineering,Xi'an Jiaotong University,Xi'an ¡¡710049,China)
Abstract:Based on the characteristics of a discharge process in a scroll air compressor,the reasonable simplification of the actual physical model was conducted and the three-dimension quasi-steady turbulent flow numerical simulation was performed.The numerical results show that complex vortex flow patterns exist in the discharge region throughout the entire axial extent of central chamber.Moreover the axial velocity component is very large at a small axial distance of 0-10 mm from the discharge port (when the height of the profile is 52 mm),and the axial velocity is greater than the radial velocity by an order of magnitude.On the basis of our numerical results,the dimensionless pressure loss coefficient was defined and the pressure loss at various crank angles after the onset of discharge was analyzed.It is shown that the discharge flow loss mainly occurs at the onset stage of discharge. The present result gives a new viewpoint that maximum area of discharge port is not always the best for designing the discharge port of a scroll compressor. The easier to open,the better the characteristic of discharge port is.
Keywords:scroll air compressor;discharge port;numerical simulation