scholarly journals The Efficiency of Mobile Hydraulic System with Diesel Engine and Axial Piston Pump Analysis

2021 ◽  
Vol 9 ◽  
Author(s):  
Murat Kapsiz ◽  
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Power Unit ◽  
Hydraulic System ◽  
Co2 Emission ◽  
Power Loss ◽  
Piston Pump ◽  
Hydraulic Systems ◽  
Axial Piston Pump ◽  
Axial Piston

Hydraulic systems are used in a wide variety of applications, stationary as well as mobile. Hydraulic pumps und motors are in many cases used for both propulsion and various work functions and is thus often a significant user of energy. Efficiency performance of a mobile hydraulic systems over a wide range of pressure and speed conditions is crucially important for power unit to save energy. In this study, efficiency of a mobile hydraulic system are studied. Mobile hydraulic system is equipped with diesel engine as power unit and axial piston pumps used for hydraulic power. The relationships between the efficiency of the axial piston pump and the power loss, the efficiency of diesel engine and the output power were explained by graphics. The average power loss of axial piston pump have changed from 0.1 kW to 2.5 kW. Losses of an axial piston pump have been determined thus fuel consumption and CO2 emission caused by these losses were shown by graph. The CO2 emission affected by the increase in pressure and speed, it reached from 5.231 kg/h to 5.61 kg/h. The research focused on analysis for axial piston pump in mobile applications, with emphasis on pump losses, fuel consumption and CO2 emission.

scholarly journals Research on Control Methods for the Pressure Continuous Regulation Electrohydraulic Proportional Axial Piston Pump of an Aircraft Hydraulic System

2019 ◽  
Vol 9 (7) ◽  
pp. 1376
Author(s):  
Peng Zhang ◽  
Yunhua Li
Keyword(s):  
Feedback Linearization ◽  
Control Method ◽  
Linear Quadratic Regulator ◽  
Piston Pump ◽  
Control Methods ◽  
Hydraulic Systems ◽  
Axial Piston Pump ◽  
Linear Quadratic ◽  
Delivery Pressure ◽  
Axial Piston

The objective of this paper is to design a pump that can match its delivery pressure to the aircraft load. Axial piston pumps used in airborne hydraulic systems are required to work in a constant pressure mode setting based on the highest pressure required by the aircraft load. However, the time using the highest pressure working mode is very short, which leads to a lot of overflow lose. This study is motivated by this fact. Pressure continuous regulation electrohydraulic proportional axial piston pump is realized by combining a dual-pressure piston pump with electro-hydraulic proportional technology, realizing the match between the delivery pressure of the pump and the aircraft load. The mathematical model is established and its dynamic characteristics are analyzed. The control methods such as a proportional integral derivative (PID) control method, linear quadratic regulator (LQR) based on a feedback linearization method and a backstepping sliding control method are designed for this nonlinear system. It can be seen from the result of simulation experiments that the requirements of pressure control with a pump are reached and the capacity of resisting disturbance of the system is strong.

Power Loss of Slipper within Axial Piston Pump

2015 ◽  
Vol 779 ◽  
pp. 3-12
Author(s):  
Ze Bo Wang ◽  
Ji Hai Jiang ◽  
Yi Sun
Keyword(s):  
Power Loss ◽  
Friction Pair ◽  
Piston Pump ◽  
Axial Piston Pump ◽  
Factors Affecting ◽  
Friction Power ◽  
Swash Plate ◽  
Model Of Friction ◽  
Friction Surfaces ◽  
Axial Piston

The pair between slipper and swash-plate is an important friction pair in the axial piston pump. Due to quick relative velocity, alternating load, numerous slippers, and high contact pressure between the friction surfaces, the wear-out and fatigue failure constantly occurs, which is one of the key factors affecting reliability of the piston pump. It is of fundamental significance to investigate the mechanism of slipper power loss and to find an appropriate method to improve the lubrication of the slipper. Here, the model of friction power loss between slipper and swash-plate is established, and the friction power loss between slipper and swash-plate is solved and comparatively analysed. Finally, the correctness of theoretical analysis and simulation results are verified by experiments.

Development of an asymmetric axial piston pump for displacement-controlled system

2013 ◽  
Vol 228 (8) ◽  
pp. 1418-1430 ◽  
Author(s):  
Jiahai Huang ◽  
Hu Zhao ◽  
Long Quan ◽  
Xiaogang Zhang
Keyword(s):  
Hydraulic System ◽  
Cost Effective ◽  
Difficult Problem ◽  
Valve Plate ◽  
Piston Pump ◽  
Flow Rate Ratio ◽  
Axial Piston Pump ◽  
Controlled System ◽  
Delivery Pressure ◽  
Axial Piston

Pump-controlled systems can eliminate throttling losses and improve the work efficiency of mobile hydraulic system. But one difficult problem for that is the differential volumetric flow through a single rod cylinder which is widely used in mobile hydraulic system. Several solutions have been presented to deal with it so far, but there still has not been a cost-effective solution to it. In recent years, an asymmetric pump-controlled asymmetric cylinder strategy has been presented to deal with this problem. In order to achieve this goal, an asymmetric axial piston pump with three ports was developed in this research. The flow rate ratio of the three ports of asymmetric axial piston pump was designed as 1: γ:(1 −  γ), in which γ was the area ratio of a single rod cylinder. An important task in the development of asymmetric axial piston pump was the design of the valve plate. There were three intake/discharge slots (slots A, B, and T) in the valve plate. The pumping dynamics of a fixed displacement asymmetric axial piston pump were investigated using software package ITI-SimulationX® and the performances of its prototype were tested. Simulation and experimental results show that with careful design, a V-shaped cross-section groove at the leading side of slot T can effectively improve the performance of asymmetric axial piston pump, and delivery pressure performance of port B is better than that of port T. Therefore, port T should be linked with low-pressure sources such as accumulator, and port B can be connected to high pressure sources. This work lays a theoretical foundation for a new exploration to pump-controlled system.

Analyses of the Long-Term Performance and Tribological Behavior of an Axial Piston Pump Using Diamondlike-Carbon-Coated Piston Shoes and Biodegradable Oil

2007 ◽  
Vol 130 (1) ◽  
Author(s):  
M. Kalin ◽  
F. Majdič ◽  
J. Vižintin ◽  
J. Pezdirnik ◽  
I. Velkavrh
Keyword(s):  
Hydraulic System ◽  
Performance Enhancement ◽  
Test System ◽  
Piston Pump ◽  
Axial Piston Pump ◽  
Hydraulic Test ◽  
Actual Application ◽  
Diamondlike Carbon ◽  
Axial Piston

This work reports on the performance enhancement of a real-scale hydraulic system consisting of diamondlike-carbon (DLC)-coated components in combination with biodegradable oil in long-term experiments under conditions simulating those in an actual application. The performance of a hydraulic axial piston pump with DLC-coated piston shoes was evaluated in a newly designed, dedicated hydraulic test system using fully formulated biodegradable, synthetic ester oil. For comparison, an equal but separated hydraulic system with a conventional commercial pump and stainless-steel shoe surfaces was tested. The tests were run at 85% of the maximum pump load and an oil temperature of around 80°C for a period of 2000h, which corresponds to more than 1yr of continuous 8h∕day operation in an application. A major abrupt oxidation-induced degradation of the oil did not occur in either system; however, the oil from the system comprising the DLC-coated shoes showed noticeably and consistently better results. The wear of the DLC-coated shoes, especially during the running in, was much lower than that in the conventional steel system. Only minor polishing wear was observed on the DLC shoe’s sliding surfaces during the test period, while on the steel shoe’s surfaces, many scratches were found and some erosion of the edges was detected.

Leakage Based Condition Monitoring and Pressure Control of the Swashplate Axial Piston Pump

2019 ◽  
Author(s):  
Neeraj Kumar ◽  
Bikash Kumar Sarkar ◽  
Subhendu Maity
Keyword(s):  
Hydraulic System ◽  
Pressure Control ◽  
Piston Pump ◽  
Chamber Pressure ◽  
Leakage Flow ◽  
Axial Piston Pump ◽  
Highly Nonlinear ◽  
Displacement Pump ◽  
Variable Displacement ◽  
Axial Piston

Abstract This research mainly focused on the axial piston variable displacement pump, which is the most important part of the fluid power system. The variable displacement axial piston has been found as versatile and flexible for electro-hydraulic applications. Heavy industries such as automobile, aircraft, and mining use an axial piston pump due to its high power to weight ratio, continuous variable power transmission, low inertia, self-lubricating properties, and good controllability. The main challenges with the hydraulic system are highly nonlinear, leakages, unknown external disturbance, etc. The mathematical model of the variable displacement pump along with swashplate control has been developed. The model is used to identify the pump health condition with pressure and flow measurement, i.e., ripple pattern. The pressure and flow ripple will vary from the regular pattern due to wear and tear, i.e., increased leakage flow. The main source of the increase in leakage flow is due to wear in piston and cylinder bore. The piston chamber pressure, kinematical flow, and discharge area model of the pump has been validated with the existing results. The pump pressure control is very much essential for the enhancement of the performance of the electro-hydraulic system. In the present study, a conventional PID controller has been used as a backup to maintain system performance within the permissible faults. The electro-hydraulic system has been employed for swash-plate control of the pump to obtain desire pressure flow at the exit of the pump. MATLAB Simulink has been used for the simulation study of the pump.

Potential energy recovery scheme with variable displacement asymmetric axial piston pump

2019 ◽  
Vol 234 (8) ◽  
pp. 875-887
Author(s):  
Aihong Wang ◽  
Zhenfeng Lv ◽  
Youshan Gao ◽  
Long Quan ◽  
Jiahai Huang
Keyword(s):  
Potential Energy ◽  
Energy Recovery ◽  
Piston Pump ◽  
Hydraulic Systems ◽  
Motor Speed ◽  
Axial Piston Pump ◽  
Charge Pressure ◽  
Variable Displacement ◽  
Saving Effect ◽  
Axial Piston

Hydraulic systems are widely used in construction machinery and equipment. However, the energy efficiency of hydraulic system is low. In many cases, hydraulic systems output energy to lift the working device. During the lowering process, the potential energy is commonly wasted through the throttling loss of the control valve. Recovering the potential energy is an efficient way to improve the hydraulic system efficiency. In this article, theoretical analysis, simulation calculation, and experimental verification were used to study the energy recovery efficiency of a differential cylinder system controlled by variable displacement asymmetric axial piston pump. Meanwhile, the influence of the load, motor speed, variable displacement asymmetric axial piston pump swashplate angle, accumulator pressure and capacity, and other key parameters on the potential energy recovery efficiency and system performance was analyzed. The results show that the system energy consumption can be reduced effectively by using the potential energy recovery system. When the load, motor speed, pre-charge pressure and capacity of the accumulator, and swashplate angle are 440 kg, 1000 r/min, 2.5 MPa, 1.6 L, and ±5°, respectively, the system’s energy-saving effect can be up to 39.25%. Considering that only the vertical motion of the differential cylinder controlled by variable displacement asymmetric axial piston pump was analyzed, in future work, the corresponding parameter optimization and control strategy will be carried out to obtain good energy recovery effect, and the influence of accumulator pre-charge pressure on the energy-saving effect will be conducted.

scholarly journals Aircraft hydraulic axial piston pump fundamental pulsation and simulation

2021 ◽  
Vol 1208 (1) ◽  
pp. 012008
Author(s):  
Želimir Husnić ◽  
Remzo Dedić ◽  
Faris Ustamujić ◽  
Zlata Jelačić
Keyword(s):  
Fundamental Frequency ◽  
Health Monitoring ◽  
Hydraulic System ◽  
Pressure Pulsation ◽  
Piston Pump ◽  
Axial Piston Pump ◽  
System Health Monitoring ◽  
Predictive Approach ◽  
Hydraulic Axial Piston Pump ◽  
Axial Piston

Abstract The axial piston pump for aircraft hydraulics systems and other high pressure hydraulic system applications is presented. This paper discusses the pump’s pressure pulsation and the fundamental frequency. Pressure pulsation associated with single piston failure is explained in relation to its fundamental frequency. A predictive approach in maintenance and pump sub system health monitoring is proposed, using numerical modelling and applicable software.

scholarly journals Optimization and Influence of Micro-Chamfering on Oil Film Lubrication Characteristics of Slipper/Swashplate Interface within Axial Piston Pump

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1961
Author(s):  
Jihai Jiang ◽  
Zebo Wang
Keyword(s):  
Numerical Model ◽  
Film Thickness ◽  
Power Loss ◽  
Piston Pump ◽  
Total Power ◽  
Axial Piston Pump ◽  
Oil Film ◽  
Friction Power ◽  
Lubrication Characteristics ◽  
Axial Piston

The overturning and eccentric abrasion of the slipper worsens the lubrication characteristics and increases the friction power loss and kinetic energy consumption of the slipper/swashplate interface to reduce the axial piston pump efficiency. A coupling lubrication numerical model and algorithm and a micro-chamfering structure are developed and proposed to predict more precisely and improve the lubrication characteristics of the slipper/swashplate interface. The simulation results reveal that the slipper without micro-chamfering overturns and contacts with the swashplate, while the one with micro-chamfering forms a certain oil film thickness to prevent this contact effectively. The minimum total power loss of the slipper/swashplate interface has to be effectively ensured under the worst working conditions, such as the high pressure, the low speed, the maximum swashplate inclination angle and the minimum house pressure. The optimal micro-chamfering width and depth are 1.2 mm and 3.5 μm or C1.2-3.5, the simulation average oil film thickness of which is approximately equal to the optimal analytical value. The experimental friction power loss of the slipper/swashplate interface is basically consistent with the simulation one, confirming the correctness and effectiveness of the coupling lubrication numerical model, and the optimization method and providing the further design direction of axial piston pumps.

Sign in / Sign up

Export Citation Format

Share Document