Multi-acting Internal Curve Radial Plunger Fluid Motor Study On Dynamic Characteristics And Low Speed Stability

The multi-acting internal curve radial piston hydraulic motor was used as one of the execution components of the hydraulic system.It features low-speed large torque,the higher volume efficiency and the higher mechanical efficiency,and is widely used in the fields of construction machinery,mining machinery and ship deck machinery and other fields.However,due to the higher work pressure of the motor with the large output torque.It is easy to disconnect from oil distribution,which causes "crawling" and oil shocks when working at a lowspeed,thus seriously affecting the working performance and service life of the motor.This article takes 16 plunger 10 radial plunger hydraulic motors as research objects.According to the structural and working characteristics of this type of hydraulic motor,an AMESim simulation model is built to analyze the dynamic characteristics of the motor and plunger,which provides a reference for further research on the motor.And use AMESim and Simulink software for co-simulation to calculate the minimum stable speed of the multi-acting internal curve motor,and analyze the influence of external key factors on the low-speed stability of the motor.The specific research work is as follows:1.The kinematic law of the motor plunger group is analyzed,and the relative motion acceleration,relative motion speed and radial displacement increment of the plunger group are calculated under the condition that the theoretical speed of the motor and the output torque ripple are zero.The stator ring curve equation and distribution plate flow area function are deduced,and the corresponding curves are solved and drawn in MATLAB software.2.Using the Cam designer in the AMESim software,a disc-shaped roller cam sub-module with the same curve as the motor stator ring was created,and an AMESim simulation model of a 16-piston 10-acting radial piston hydraulic motor was built.The theoretical calculation results and simulation results of the motor speed and output torque are compared and analyzed to verify the correctness and reliability of the motor simulation model.3.Dynamic analysis of the motor speed under different inlet flow rates,output torque under different working pressures,and total working efficiency characteristics are carried out,and the dynamic characteristics of the motor under different working parameters are compared.Under the condition that the motor inlet flow is rated flow,analyze the change rule of the inlet flow,pressure,plunger torque and plunger clearance leakage of the plunger cavity.4.Under the condition of considering the motor friction torque,the mathematical model of the multi-action internal curve motor is established by Simulink software,and the co-simulation with AMESim software is carried out to calculate the minimum stable speed of this type of motor to be 3.2 r/min.The degree of influence of key factors such as load,oil gas content,oil temperature and oil viscosity on the low-speed stability of the motor.