The research on the oil film characteristic of piston pair is beneficial to the design and optimization of friction pair,which can improve the performance of piston pump.The fluid pressure of piston cavity is accurate...The research on the oil film characteristic of piston pair is beneficial to the design and optimization of friction pair,which can improve the performance of piston pump.The fluid pressure of piston cavity is accurately obtained by AMEsim simulation.Oil film thickness field model of piston pair under the slanting state of piston is established,and the distribution law is numerically analyzed under different speed and pressure by Matlab.The experiment model pump for oil film characteristic of piston pair is designed to measure oil film thickness under the pressure of 18 MPa.The experiment results show that oil film thickness varies greatly under high pressure,and oil film thickness fluctuates sharply under low speed.The minimum oil film thickness increases with spindle speed increasing and oil film characteristic of piston pair based on the numerical analysis method is verified.This method lays a foundation for studying the friction performance of piston pair in the axial piston pump.展开更多
The positive pressure between pistonwall and piston hole of inner curve water hydraulic motor’s piston pairs is analyzed.The flow field of the piston pairs is numerically calculated and analyzed by the use of computa...The positive pressure between pistonwall and piston hole of inner curve water hydraulic motor’s piston pairs is analyzed.The flow field of the piston pairs is numerically calculated and analyzed by the use of computational fluid dynamics method.The pressure and velocity distribution of flow field at different clearance is analyzed in the paper.The results show that when the clearance is 4-8 μm,with the increase of clearance,the negative pressure and the velocity of piston chamber decrease significantly,the velocity and leakage flow of the clearance increase.However,when the clearance is 10 μm,the negative pressure and the velocity of plunger chamber increase suddenly.By comprehensive analysis,the cylinder annular clearance should be controlled to be near 8 μm.展开更多
The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key fri...The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key friction pairs are always a key and difficult problem in the research on axial piston pump. In the traditional research on piston/cylinder pair, the assembly relationship of piston and cylinder bore is simplified into ideal cylindrical pair, which can not be used to analyze the influences of radial micro-motion of piston on the distribution characteristics of oil-film thickness and pressure in details. In this paper, based on the lubrication theory of the oil film, a numerical simulation model is built, taking the influences of roughness, elastic deformation of piston and pressure-viscosity effect into consideration. With the simulation model, the dynamic characteristics of the radial micro-motion and pressure distribution are analyzed, and the relationships between radial micro-motion and carrying ability, lubrication condition, and abrasion are discussed. Furthermore, a model pump for pressure distribution measurement of oil film between piston and cylinder bore is designed. The comparison of simulation and experimental results of pressure distribution shows that the simulation model has high accuracy. The experiment and simulation results demonstrate that the pressure distribution has peak values that are much higher than the boundary pressure in the piston chamber due to the radial micro-motion, and the abrasion of piston takes place mainly on the hand close to piston ball. In addition, improvement of manufacturing roundness and straightness of piston and cylinder bore is helpful to improve the carrying ability of piston/cylinder pair. The proposed research provides references for designing piston/cylinder pair, and helps to prolong the service life of axial piston pump.展开更多
基金Supported by the National Natural Science Foundation of China(No.51975164)the Fundamental Research Foundation for Universities of Heilongjiang Province.
文摘The research on the oil film characteristic of piston pair is beneficial to the design and optimization of friction pair,which can improve the performance of piston pump.The fluid pressure of piston cavity is accurately obtained by AMEsim simulation.Oil film thickness field model of piston pair under the slanting state of piston is established,and the distribution law is numerically analyzed under different speed and pressure by Matlab.The experiment model pump for oil film characteristic of piston pair is designed to measure oil film thickness under the pressure of 18 MPa.The experiment results show that oil film thickness varies greatly under high pressure,and oil film thickness fluctuates sharply under low speed.The minimum oil film thickness increases with spindle speed increasing and oil film characteristic of piston pair based on the numerical analysis method is verified.This method lays a foundation for studying the friction performance of piston pair in the axial piston pump.
基金Supported by the National Natural Science Foundation of China (No.51505111)China Postdoctoral Science Foundation (No.2020M681844)Zhejiang Province Postdoctoral Science Foundation (No.ZJ2020043)。
文摘The positive pressure between pistonwall and piston hole of inner curve water hydraulic motor’s piston pairs is analyzed.The flow field of the piston pairs is numerically calculated and analyzed by the use of computational fluid dynamics method.The pressure and velocity distribution of flow field at different clearance is analyzed in the paper.The results show that when the clearance is 4-8 μm,with the increase of clearance,the negative pressure and the velocity of piston chamber decrease significantly,the velocity and leakage flow of the clearance increase.However,when the clearance is 10 μm,the negative pressure and the velocity of plunger chamber increase suddenly.By comprehensive analysis,the cylinder annular clearance should be controlled to be near 8 μm.
基金supported by National Natural Science Foundation of China(Grant No. 51075360)Doctoral Foundation of Ministry of Education of China(Grant No. 20090101110041)National Key Technology R&D Program of the Twelfth Five-year Plan of China(Grant No. 2011BAF09B03)
文摘The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key friction pairs are always a key and difficult problem in the research on axial piston pump. In the traditional research on piston/cylinder pair, the assembly relationship of piston and cylinder bore is simplified into ideal cylindrical pair, which can not be used to analyze the influences of radial micro-motion of piston on the distribution characteristics of oil-film thickness and pressure in details. In this paper, based on the lubrication theory of the oil film, a numerical simulation model is built, taking the influences of roughness, elastic deformation of piston and pressure-viscosity effect into consideration. With the simulation model, the dynamic characteristics of the radial micro-motion and pressure distribution are analyzed, and the relationships between radial micro-motion and carrying ability, lubrication condition, and abrasion are discussed. Furthermore, a model pump for pressure distribution measurement of oil film between piston and cylinder bore is designed. The comparison of simulation and experimental results of pressure distribution shows that the simulation model has high accuracy. The experiment and simulation results demonstrate that the pressure distribution has peak values that are much higher than the boundary pressure in the piston chamber due to the radial micro-motion, and the abrasion of piston takes place mainly on the hand close to piston ball. In addition, improvement of manufacturing roundness and straightness of piston and cylinder bore is helpful to improve the carrying ability of piston/cylinder pair. The proposed research provides references for designing piston/cylinder pair, and helps to prolong the service life of axial piston pump.
