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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 purpose of this study is to determine the cavitation flow characteristics of the high-pressure differential control valve. The relationship between cavitation, flow coefficient and spool angle is obtained. By analyzing the relationship between different spool angles and energy loss, the energy loss at different spool angles is predicted.

A series of numerical simulations were performed to study the cavitation problem of a high-pressure differential control valve using the RNG k–e turbulence model and the Zwart cavitation model. The flow states and energy distribution at different spool angles were analyzed under specific working conditions.

The cavitation was the weakest when the spool angle was 120° or the outlet pressure was 8 MPa. The pressure and speed fluctuations of the valve in the throttle section were greater than those at other locations. By calculating the entropy production rate, the reason and location of valve energy loss are analyzed. The energy loss near the throttling section accounts for about 92.7% of the total energy loss. According to the calculated energy loss relationship between different regions of the spool angle, the relationship between any spool angle and energy loss in the [80,120] interval is proposed.

This study analyzes the cavitation flow characteristics of the high-pressure differential control valve and provides the law of energy loss in the valve through the analysis method of entropy. The relationship between spool angle and energy loss under cavitation is finally proposed. The research results are expected to provide a theoretical basis for the optimal design of valves.

Reports on the progress made and problems experienced by the University of Hull while working in conjunction with J.H. Turner to develop a prototype water‐powered robot.

REPORT numbered XXXI‐41 prepared by the Combined Intelligence Objectives Sub‐Committee contains information on the hydraulic systems of three German aircraft, the Dornier 335 and Messerschmitt 262 and 410. In the expectation that readers who have had no opportunity of studying the report itself will welcome a description of these systems, it is proposed to supplement the review given in the July issue of this journal by more detailed abstracts from the report. The Me 262 and Me 410 will be dealt with in this article, leaving the Do 335 for a later date.

Globe valves have good throttling ability, which permits its use in regulating flows. This paper aims to understand in detail the globe valve with different cage configurations and its impact on the flow characteristics that was carried out.

The computational study was carried out using FLUENT, a finite volume-based numerical code. Grid sensitivity tests were done and the results were validated experimentally. The effect of cage configuration on flow characteristics and valve coefficient was studied and optimised.

Valve coefficient was found to be dependent on cage configuration and reaches its maximum for the valve with triangular shaped aperture. Methodology to improve flow performance of a globe valve with highest valve coefficient is established.

Studies related with caged-type globe valves having different configurations are useful for improving their flow performance. In the present investigation, globe valves with different cage configurations and throttle positions are modeled to find out the valve coefficient, pressure and velocity contours inside and outside the cage and is validated with experimental results.

ALTHOUGH assisted by such agencies as aerodynamic drag and engine reverse thrust, slowing and stopping a modern aircraft on the ground is achieved principally by the use of wheel brakes to generate a horizontal drag force between the tyres and the ground. In the braking process the aircraft kinetic energy is converted to heat energy in the brakes by the application of hydraulic power to the brake discs to create friction. The heat energy is dissipated by natural or forced cooling.

AS is to be expected, the various systems on the Trident 2E closely follow those evolved for the Tridents 1 and 1E, except for the changes in the fuel system necessitated by the introduction of the fin fuel tank, and the embodiment of a turbine‐compressor type of cold air unit in the air conditioning system.

THE S‐3A VEHICLE is equipped with 2 completely independent hydraulic systems which have been designated as the combined flight control/utility system. These systems are both structurally and hydraulically isolated from each other and are designed and installed in accordance with spec. MIL‐H‐5440 type II (−65° to 275°F temperature range) class 3000 (cutout pressure at pump is 3,100psi).

In combination with dirigible craft provided with means for directing the same, power mechanism for actuating said directing means and means sensitive to turn of the craft, means for integrating the extent of turn and a separate device sensitive to acceleration, all connected to conjonitly control operation of said power mechanism.

This study aims to develop a new design for the fluid-safety valve to make it more environmentally friendly.

Computational fluid dynamics is carried out to analyse the behaviour of flow in both traditional and new safety valves.

The possibility of failure in the new design under the maximum allowable working pressure is analysed using finite element analysis.

Investigating a new low-fluid pressure safety valve design.