Research On The Effect Of Anti-rotation Mechanism Clearance On The Tangential Leakage Of Scroll Compressor

Scroll compressor as a new generation of volumetric fluid machinery,compared with other traditional compressors has the advantages of simple structure,small volume,high efficiency,high reliability and environmental protection and energy saving,is widely used in industry,agriculture,transportation,medical and other fields requiring gas compression.As one of the important parts of scroll compressor,the anti-rotation mechanism restricts the freedom of the moving scroll disk,and makes the moving scroll disk do revolution translational motion with respect to the static scroll disk.Cross slip ring anti-rotation mechanism is widely used because of its simple manufacturing process,easy assembly and high reliability,but the motion characteristics determine that there are friction pair gaps between it,the moving vortex disk and the bracket body.In this paper,a cross slip ring scroll compressor is taken as the research object,and the influence of friction pair clearance on tangential leakage of working chamber of the scroll compressor with fixed radius of rotation is studied and analyzed by combining theoretical calculation and numerical simulation.Firstly,according to the structure and working principle of scroll compressor,the force model of the cross slip ring and the moving vortex disk is studied theoretically,the simplified mechanism model of the compressor component is established,and the motion law of the cross slip ring and the moving vortex disk is obtained.Secondly,based on the simplified mechanism model of the compressor,combined with the dynamic characteristics of the cross slip ring and the moving disc,the slight rotation phenomenon of the moving disc caused by the gas force in the compression chamber was analyzed.The rotation torque under the action of dynamic vortex disk from the Angle of the theoretical calculation formula,established the cross slip ring friction pair clearance and the mathematical model of the tangential leakage clearance variation,the crankshaft rotating week anti-rotation mechanism caused by the tangential friction pair clearance leakage clearance variation are analyzed and discussed,it is concluded that the tangential leakage clearance variation in the crank Angle is 90° and 270° mutations,The maximum change of tangential leakage clearance is 0.0803 mm.A mathematical model of tangential leakage was established,and the maximum tangential leakage caused by the clearance of the friction pair of the cross slip ring in the adjacent compression chamber was calculated,which provided a theoretical basis for the structural optimization design and performance improvement of scroll compressor.Finally,for tangential leakage caused by rotation of moving vortices under different clearance of friction pairs,geometric models of tangential leakage corresponding to different clearance of friction pairs were established.Through simulation calculation by FLUENT software,the variation rules of pressure field,velocity vector field and leakage amount of tangential leakage model under different friction pair clearance are obtained,and the results of theoretical calculation and numerical simulation are compared and analyzed.It is concluded that the tangential leakage increases with the increase of the clearance of friction pair.When the clearance of friction pair increases from 0.02 to 0.08,the tangential leakage increases about 1.575 times.The pressure loss caused by gas flow between adjacent compression cavities increases with the increase of leakage gap and pressure difference between adjacent compression cavities.The clearance of friction pair of slip ring and the pressure difference between adjacent working chamber are the common reasons affecting tangential leakage.