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High pressure and high speed of the axial piston pump can improve its power density, but they also deteriorate the thermal-fluid-structure coupling effect of the friction pairs. This paper aims to reveal the coupling mechanism of the pump, for example, valve plate pair, by carrying out research on multi-physics field coupling.

Considering the influences of temperature on material properties and thermal fluid on structure, the thermal-fluid elastic mechanics model is established. A complete set of fast and effective thermal-fluid-structure coupling method is presented, by which the numerical analysis is conducted for the valve plate pair.

According to calculations, it is revealed that the temperature and pressure evolution laws of oil film with time, the pressure distribution law of the fluid, stress and displacement distribution laws of the solid in the valve plate pair. In addition, the forming history of the wedge-shaped oil film and mating clearance change law with rotational speed and outlet pressure in the valve plate pair are presented.

For an axial piston pump operating under high speed, high pressure and wide temperature range, the multi-physics field coupling analysis is an indispensable means and method. This paper provides theoretical evidence for the development of the pump and lays a solid foundation for the research of the same kind of problem.

The drive shaft and the distribution shaft of a traditional radial piston pump are in a cantilever state. To solve this problem, this paper aims to present a radial piston pump with through shaft driving and valve plate distribution.

The working principle of the pump is discussed in detail. In this radial piston pump, valve plate distribution parts are designed to distribute oil to the piston chambers, and the distribution shaft is replaced. A bearing is installed between the stator and rotator to reduce the friction. The transmission shaft is supported by two bearings to ensure smooth operation. The support force of the transmission shaft is optimized. In addition, the flow pulsation principle is presented. To accomplish the change, the displacement of the radial piston pump, the proportional control system is designed.

After completing the machining and assembly of the pump, an experimental study was carried out. The results show that the output flow of the pump is basically the same as the theoretical flow.

The friction between the slipping shoes and the stator is greatly reduced due to the function of rolling bearings. The higher stability of the driveshaft is obtained for the reason of double-sided support. The radial piston pump has a novel structural design in reducing the friction between the shoes and the stator and improving the stability of the transmission shaft.

The purpose of this paper is to study the effects of single parameters for temperature characteristics of oil film in port plate pair and the relationship of calculated results and experimental results under different viscosity.

The paper established the mathematical model of oil film of port plate pair, calculated the energy equation of port plate pair, simulated for the oil film and temperature distribution and selected different kinds of lubricants to analyze the calculated value and the experimental value.

The results show: temperature rise of port plate pair is reduced with the increase of oil viscosity; temperature rise of port plate pair is decreased with rise of initial oil film thickness; temperature rise of port plate pair is increased with the rise of cylinder body speed, inclination angle and sealing belt width; and through the comparison of calculated value and experimental value, under the same viscosity and cylinder speed, experimental results are bigger.

This paper used the methods that the temperature of port plate pair was calculated numerically, and the results were consistent with experimental results, so it can get high precision.

The purpose of this paper is to analyze the micro-motion of the cylinder block.

Based on the elasto-hydrodynamic lubrication, a numerical model for the cylinder block/valve plate interface is proposed, with consideration of the elastic deformations, the pressure-viscosity effect and asperity contacts. The influence-function method is applied to calculating the actual deformations of the cylinder block and the valve plate. The asperity contact model simplified from Greenwood assumption is introduced into the numerical model. Furthermore, the relationship between the micro-motion and the operating condition, the sealing belt width is discussed, respectively.

The results show an increase in the discharge pressure causes the tilt state and the vibrating motion getting worse, which can be eased by improving the rotational speed, the sealing belt width and the ratio of external and internal sealing belt width.

The proposed research can provide a theoretical reference for the optimizing design of cylinder block/valve plate pair.

The purpose of this paper is to analyze the cavitation characteristics of a water hydraulic axial piston motor (WHAPM) to improve the water motor performance, to reduce the vibration and noise and to prolong the service life of the motor.

The computational fluid dynamics (CFD) software PumpLinx is chosen to do cavitation analysis of the WHAPM. In this case, first, cavitation mechanism of the water piston motor is analyzed in depth. Then, considering the effects of bubble dynamics, the rate of phase transition, turbulence effects and non-condensable gas, the full cavitation model is selected, the dynamic CFD numerical model of internal flow field on the water hydraulic piston motor is established based on PumpLinx software and the fluid cavitation inside is numerically studied. Finally, the influence of the valve plate and pistons on motor cavitation is analyzed.

Research results show that there are two serious cavitation regions: one is the pressure transition region of the valve plate that is near the top dead center, and the other is the low-pressure region of the piston that is near the low-pressure transition area. Moreover, the more serious cavitation area is on the valve plate region.

The simulation results show that the proposed algorithm is able to detect the cavitation characteristics of the water piston motor. Besides, it is deduced that valve-plate structure optimization is more important than pistons to reduce cavitation influence.

The sensitivity of differential‐pressure flow meters to the quality of the approaching flow continues to be a cause for concern to flow meter manufacturers and users. Distortions to the approaching velocity profiles generated by pipe fittings and installations located upstream of a flow meter, can lead to considerable errors in flow metering. This cannot be ignored because of the likely cost and process efficiency implications. This paper describes the effects of various entrance flow velocity profiles on the performance of an orifice flow meter with and without flow conditioning. Asymmetric swirling velocity profiles were generated by a ball valve. These caused significant shifts to the meter’s calibration. The use of a vaned‐plate flow conditioner, consisting of six vanes attached to a 70 per cent porosity plate, greatly improved the performance of the meter. Thus, the device can be used as part of a flow metering package that will have considerably reduced installation lengths. The less‐sophisticated NEL plate proved to be a good flow straightener, i.e. a good swirl remover, but was not an efficient flow conditioner.

The purpose of this study is to explore the transient characteristics of mixed-flow pumps during startup process.

This study uses a full-flow field transient calculation method of mixed-flow pump based on a closed-loop model.

The findings show the hydraulic losses and internal flow characteristics of the piping system during the start-up process.

Large computational cost.

Improve the accuracy of current numerical simulation results in transient process of mixed-flow pump.

Simplify the setting of boundary conditions in the transient calculation.

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

This paper aims to propose the slipper/swash plate pair loaded with a step motor-spring mechanism to reduce the energy consumption under different rotating rate conditions. The relationship between the operating conditions, oil film thickness and energy consumption is analyzed. The system dynamic model of the slipper/swash plate pair loaded with a step motor-spring mechanism is introduced. Based on the results of the experiment, the PI controller and step motor-spring mechanism are useful for reducing energy consumption.

This paper introduces the energy consumption of the slipper/swash plate pair. A system dynamic model of the slipper/swash plate pair loaded with a step motor-spring mechanism is introduced too. In the experiment, three step motor and S-type force sensor are used to control the oil film thickness.

PI controller and the step motor-spring mechanism are useful for controlling the oil film thickness and reducing the energy consumption under different rotating rate conditions. The accuracy of the oil film thickness control is acceptable and the response time is a bit long

PI controller and the step motor-spring mechanism are useful for controlling the oil film thickness and reducing the energy consumption under different rotating rate conditions. The accuracy of the oil film thickness control is acceptable and the response time is a bit long.

The study aims to decrease the effect of solid particles on a butterfly valve, which will cause seal failure and leakage, providing a reference for anti-wear design.

In this paper, computational fluid dynamics discrete element method (CFD-DEM) simulation was conducted to study the solid–liquid two-phase flow characteristics and erosion characteristics of a butterfly valve with a different opening.

Abrasion at 10% opening is affected by high-speed jets in upper and lower parts of the pipeline, where the erosion is intense. The impact of the jet on the upper part of 20% opening begins to weaken. With the top backflow vortex disappearing, the effect of lower jet is enhanced. Meanwhile, the bottom backflow vortex phenomenon is obvious, and the abrasion position moves downward. At 30% opening, the velocity is further weakened, and the circulation effect of lower flow channel is more obvious than that of the upper one.

It is the first time to use DEM to investigate the two-phase flow and erosion characteristics at a small opening of a butterfly valve, considering the effect of inter-particle collision. Therefore, this study carries on the thorough analysis and discussion. At the same opening degree, with increasing of the particle size, the abrasion of valve frontal surface increases when the size is less than 150 µm and decreases when it is greater than 150 µm. For the valve backflow surface, this boundary value becomes 200 µm.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2020-0264/