Theoretical Research And Design On Rotary Vane Compressor

The subject comes from state key laboratory of mechanical transmission fund(Item Number: SKLMT-KFKT-200905).At present, rotary vane compressor has become the mainstream of air refrigerationcompressor used in automotive. The design theory on cylinder profile suited forblade-centre rotary vane compressor lacks generality, the research creatively made thedesign of cylinder boiled down to the establishment of motion law of vane, polynomialmotion law curve of vane was constructed which had advantages in reducing leakage ofclearance between cylinder and rotor and expanding the volume of working cavity,cylinder profile could be obtained which satisfied the motion law of vane according tothe mathematical relationship between cylinder profile and the motion of vane.According to the inverse solution, the design for the geometric figure of back pressurecavity could be boiled down to the establishment of mathematic model of back pressure,which was obtained by assuming the contact force acted between the inner of cylinderand the top of vane, the purpose was to decrease fictional power consumption andimprove the stress state of vane, then get a better performance of rotary vanecompressor. The main work was as follows:Analyzed the advantage of blade-offset rotary vane compressor, according to theenvelope principle of isometric curve, the motion of vane was simplified to the motionof the centre of the arc on top of vane, then established the motion model of vane, therelationship between the displacement、velocity、acceleration of vane and varied angleof rotor was put forward. Simulated analysis for the theory above was done. The methodavoided the complicated process but could get the detailed position of contact pointbetween cylinder and vane, the dependable theoretical calculation for vane-offset rotaryvane compressor which was widely used in automobile could be obtained. The result ofnumerical simulated analysis based on MATLAB proved the precision of the work. Dueto feature of the vane motion both in vane-centre and vane-offset compressor was varydifferent, the vane motion of vane-offset compressor could not be analyzed by themethod applied for vane-centre compressor. Otherwise, the feather of kinematics anddynamics of cylinder profile could not be reflected truly.Design of cylinder profile can be boiled down to the establishment of motion lawof vane, polynomial motion law curve of vane was constructed which had advantages in reducing leakage of clearance between cylinder and rotor and expanding the volume ofworking cavity, cylinder profile could be obtained which satisfied the motion law ofvane according to the mathematical relationship between cylinder profile and themotion of vane. Compared to traditional vane compressor whose cylinder profile washarmonic curve, the vane compressor which was evolved by the polynomial motion lawof law had better performance in minimizing the clearance between cylinder and rotorbased on ensuring the dynamic characteristic curve of vane fluent and successive aswell as expanding the inhaling volume and exhaling volume under the condition of thesame structure parameters.The new mathematical model for the basic volume in vane-offset rotary vanecompressor was established and analyzed, researched and compared the basic volumeboth in innovative compressor and traditional compressor, stated the inhaling volume ofinnovative compressor was higher than traditional compressor under the condition ofthe same structure parameters.Reduce the contact force between cylinder and vane under the condition ofensuring the top of vane reached the cylinder inner can help decrease the fictionalconsumption and improve the performance of compressor, set zero contact force andcalculated forces acted on vane, analyzed the variety of forces with rotational rate ofrotator respectively, particularly back force acted on vane which was close related tocontact force, the constrained force acted by vane slot varied little with the angle, whilethe back force decreased when rotational rate increased. Provided theoretical foundationfor the proper design of back pressure cavity.Developed an aided design and analysis system on rotary vane compressor basedon C++Builder, the data could exchange with each other, any change of designparameters could be reflected by the object-oriented interface, which simplified thedesign and analysis process, provided a powerful tool for the design of innovative rotaryvane compressor.