Fluid-structure interaction analysis of the return pipeline in the high-pressure and large-flow-rate hydraulic power system

In this paper, a 3-D fluid-structure interaction (FSI) analysis on the performance of the high-pressure fuel pump for diesel engines is presented. The fluid and structure are two-way coupled and several complex factors are taken into accounts in the FSI model. For instance, the fluid model includes not only the high-pressure fuel pump but also the rail and pressure-control valve which are used to maintain a stable delivery pressure of the pump; Gap boundary condition is adopted to simulate the opening and closing of the valve; The flow is assumed to be nonisothermal and the physical properties of the fuel such as dynamic viscosity and density are functions of pressure and temperature. While in the structure model, the spring force on the valve and the contacts between the valve and the valve seat as well as the top block are considered. The calculated volumetric efficiency losses agree well with the experiments, which indicates that the FSI model established in this study could well predict the physical phenomenon taking place in the high-pressure fuel pump. Several new conclusions can be drawn from the discussions on the results such as the suction efficiency loss due to the delay closing of the inlet valve is extremely small while the suction loss due to the expansion of the high-pressure fuel entrapped in the dead volume is very large.

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A Nonisothermal Fluid-Structure Interaction Analysis on the Piston/Cylinder Interface Leakage of High-Pressure Fuel Pump

Journal of Tribology ◽

10.1115/1.4026501 ◽

2014 ◽

Vol 136 (2) ◽

Cited By ~ 9

Author(s):

Dexing Qian ◽

Ridong Liao

Keyword(s):

High Pressure ◽

Interaction Analysis ◽

Fluid Structure Interaction ◽

Fluid Pressure ◽

Leakage Rate ◽

Fluid Structure ◽

Structure Interaction ◽

Piston Cylinder ◽

Piston Pair ◽

Nonisothermal Fluid

In this paper, a nonisothermal fluid-structure interaction mathematical model for the piston/cylinder interface leakage is presented. Full account is taken of the piston eccentricity, elastic deformations of the piston pair, the nonisothermal flow in the interface, and the physical properties of the fluid such as the pressure-viscosity and temperature-viscosity effects. The numerical method for the solution of the model is given, which can simultaneously solve for the fluid pressure distribution and leakage rate in the interface. The model is validated by comparing the calculated leakage rates with the measurements. Results show the good accuracy of the model. The impacts of parameters such as the piston diameter, the initial clearance between the piston pair, and the piston velocity on the leakage rate are discussed. Some of the conclusions provide good guidance for the design of high-pressure fuel pumps.

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Fluid-Structure Interaction Analysis on Membrane Behavior of a Microfluidic Passive Valve

Membranes ◽

10.3390/membranes10100300 ◽

2020 ◽

Vol 10 (10) ◽

pp. 300 ◽

Cited By ~ 1

Author(s):

Zhen-hao Lin ◽

Xiao-juan Li ◽

Zhi-jiang Jin ◽

Jin-yuan Qian

Keyword(s):

Fluid Flow ◽

Flow Rate ◽

Interaction Analysis ◽

Fluid Structure Interaction ◽

Flow Characteristics ◽

Microfluidic System ◽

Membrane Behavior ◽

Fluid Structure ◽

Constant Flow Rate ◽

Structure Interaction

In this paper, the effect of membrane features on flow characteristics in the microfluidic passive valve (MPV) and the membrane behavior against fluid flow are studied using the fluid-structure interaction (FSI) analysis. Firstly, the microvalve model with different numbers of microholes and pitches of microholes are designed to investigate the flow rate of the MPV. The result shows that the number of microholes on the membrane has a significant impact on the flow rate of the MPV, while the pitch of microholes has little effect on it. The constant flow rate maintained by the microvalve (the number of microholes n = 4) is 5.75 mL/min, and the threshold pressure to achieve the flow rate is 4 kPa. Secondly, the behavior of the membrane against the fluid flow is analyzed. The result shows that as the inlet pressure increases, the flow resistance of the MPV increases rapidly, and the deformation of the membrane gradually becomes stable. Finally, the effect of the membrane material on the flow rate and the deformation of the membrane are studied. The result shows that changes in the material properties of the membrane cause a decrease in the amount of deformation in all stages the all positions of the membrane. This work may provide valuable guidance for the optimization of microfluidic passive valve in microfluidic system.

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