scholarly journals Modeling and Performance Improvement of the Constant Power Regulator Systems in Variable Displacement Axial Piston Pump

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Sung Hwan Park ◽  
Ji Min Lee ◽  
Jong Shik Kim

An irregular performance of a mechanical-type constant power regulator is considered. In order to find the cause of an irregular discharge flow at the cut-off pressure area, modeling and numerical simulations are performed to observe dynamic behavior of internal parts of the constant power regulator system for a swashplate-type axial piston pump. The commercial numerical simulation software AMESim is applied to model the mechanical-type regulator with hydraulic pump and simulate the performance of it. The validity of the simulation model of the constant power regulator system is verified by comparing simulation results with experiments. In order to find the cause of the irregular performance of the mechanical-type constant power regulator system, the behavior of main components such as the spool, sleeve, and counterbalance piston is investigated using computer simulation. The shape modification of the counterbalance piston is proposed to improve the undesirable performance of the mechanical-type constant power regulator. The performance improvement is verified by computer simulation using AMESim software.

2013 ◽  
Vol 328 ◽  
pp. 629-633
Author(s):  
Ya Jun Wang

A method is implemented to get the pressure distribution of the axial piston pump slipper. Slipper was seen as translating thrust bearing, taking slipper tilt and spin in account, based on finite volume method, hydrodynamic and hydrostatic pressure has been calculated by using the mass conservation principle. For a representative element volume, the difference flow was averaged by the difference flow between the tilting planes, and the shearing flow by slipper translating was averaged by the shearing flow between the tilting planes. The numerical calculating result based two liquid resistance assume was compared, the results showed that two methods have got the same pressure distribution schematics, and the high pressure area locates at the slipper titling direction, but for the pressure values at high pressure area, the second method is slightly higher than the first method, and that the higher pump speed were, the higher the pressure values, and at the same pump speed, the slipper spin speed affects slightly the pressure, and at the lower pump speed, the lubricant pressure tends to the hydrostatic lubrication.


Author(s):  
Yang Pan ◽  
Yibo Li ◽  
Dedong Liang

The vibration of a swash plate is caused by the piston forces and the control actuator acting on the swash plate. An earlier study of the outlet flow ripple of variable-displacement axial piston pumps assumed a fixed swash plate angle; it ignored the influence of swash plate vibration on the outlet flow ripple of the axial piston pump. In this work, a theoretical model of the outlet flow ripple and pressure pulsation was established in a constant power variable-displacement piston pump. The vibration of swash plate, flow leakage, and valve dynamic characteristics are considered in the theoretical model. The computational results of the theoretical model at different external load pressures are verified by comparison with experimental results. The vibration of the swash plate is strongly influenced by both the piston chamber pressure variation and the control actuator mechanism. The study proved the influence of the swash plate vibration on the outlet flow ripple and the pressure pulsation of an axial piston pump. Compared to the case of a fixed swash plate angle, accounting for swash plate vibration is much more suitable for the accurate determination of the outlet flow ripple and pressure pulsation of an axial piston pump. It is also shown that the vibration of the swash plate affects the valve plate design. Accordingly, valve plate optimization based on the theoretical model of the outlet flow ripple was also studied in this work. The amplitude of the instantaneous outlet flow ripple was considered as the optimization objective function. Finally, the optimized design parameters for a constant power variable-displacement swash plate axial piston pump were evaluated.


2010 ◽  
Vol 42 ◽  
pp. 43-47 ◽  
Author(s):  
Lei Li ◽  
Ming Heng Xu ◽  
Jian Ke ◽  
Lan Ying Yu

To examine the flow characteristic of axial piston pump with conical cylinder block, a comprehensive mathematical model of flow condition within a single cylinder bore was developed by utilizing discrete approximation. Each step of the discrete analog was fallen into three successive phases with oil compressibility and classical orifice equation. Besides, the discharge flow equation of whole pump was obtained with lumped parameter method. Based upon this model, a simulation system was built in the simulation software. The novel aspect of this research is that analysis of cylinder block cone angle. From the result of numerical simulation, it can be concluded that cylinder block cone angle has a significant impact on the flow characteristics, and conical cylinder block design is more feasible than cylindrical cylinder block from a flow characteristic point of view.


AIP Advances ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 115221
Author(s):  
Jihai Jiang ◽  
Boran Du ◽  
Jian Zhang ◽  
Geqiang Li

Sign in / Sign up

Export Citation Format

Share Document