Simulation And Characteristics Research Of A Constant Pressure Swashplate Piston Pump

With the rapid development of the global social economy and the continuous growth of the population,the problem of energy shortage is becoming more and more serious,so energy-saving products are increasingly welcomed and valued by people.Compared with other transmission methods,hydraulic transmission has the advantages of large output force,wide speed range,high power density and easy control.It is widely used in various fields,especially suitable for fast response and high power.In practical application,a quantitative pump and relief valve are usually used as the power source of the whole hydraulic system.And the pressure of the hydraulic system is determined by the setting pressure of the relief valve.In the standby condition of the machine,a large amount of hydraulic oil returns to the tank through the relief valve,resulting in a large amount of energy loss.However the constant pressure pump can adjust the flow of the pump according to the size of the external load,so that the outlet pressure is kept constant,avoiding unnecessary loss caused by overflow of hydraulic oil from relief valve.So it conforms to the general trend of energy saving and environmental protection nowadays.Therefore,this paper chooses the proportional constant pressure swashplate piston pump as the research object,and carries out the following research and analysis through the combination of theoretical analysis and co-simulation:1.Firstly,this paper explains the research background and significance of this project,introduces the basic concept of a plunger pump,and expounds the development status of variable plunger pump at home and abroad.Finally,the main content and methods of the research are determined.2.According to the basic working principle of a plunger pump,the theoretical formula of the flow characteristics,the motion law and the dynamic characteristics of the swash plate are analyzed and derived,and the mathematical model of the distribution area is established to obtain the theoretical expression of the distribution area.The theoretical expression of the distribution area is obtained,which provides a theoretical basis for the establishment of the main body model of a plunger pump.For the constant pressure pump studied,the working principle is analyzed,and the mathematical models such as variable cylinder and main control pressure valve in the variable mechanism are further analyzed to provide a theoretical basis for the establishment of the variable mechanism model.3.Surveying and mapping the constant pressure pump studied,establishing 3D model of the constant-pressure pump in Pro/E according to the structural data of the surveying and mapping,and establishing the one-dimensional hydraulic model of the constant pressure pump in SimulationX according to the actual physical structure,variable principle and the derived mathematical model of the constant-pressure pump.Through the CADImport module in SimulationX,the 3D model of constant pressure pump parts is imported.According to the actual constraints of each part,the corresponding constraints module is added to SimulationX to complete the establishment of multi-body dynamic model of constant pressure pump in SimulationX.Finally,the one-dimensional hydraulic model and the multi-body dynamic model are connected by the motion-force conversion module in SimulationX.The real-time mechanical-hydraulic co-simulation is realized by real-time exchange between the hydraulic model and the dynamic model to transfer the plunger chamber pressure and the plunger motion,the variable cylinder pressure and the variable cylinder motion.In summary,the SimulationX mechanical-hydraulic co-simulation model of constant pressure pump can be established.4.According to the established model of constant pressure plunger pump,the basic movement law,flow and pressure characteristics of the plunger pump and the reasons for the fluctuation of flow and pressure are first simulated and analyzed.Then the influence of the deflection angle of the distributor and the structural parameters of the triangular groove on the flow and pressure characteristics of the plunger pump is simulated and analyzed,and the optimal selection of the deflection angle of the distributor and the structural parameters of the triangular groove is obtained.Finally,the static and dynamic characteristics of a constant pressure pump are analyzed,and the influence of variable system parameters on the dynamic characteristics of a constant pressure pump is studied,which provides a basis for the selection of main parameters of variable mechanism.In this paper,the SimulationX is used to study the electro-hydraulic co-simulation of the electric proportional swash plate type constant pressure plunger pump.The pressure flow characteristics,variable control characteristics and the influence of different parameters on the characteristics of the constant pressure pump are analyzed.The further improvement and optimization of the structural parameters of the plunger pump provides theoretical support and has certain reference value for the actual development of the constant pressure pump.