Papers by Keyword: Fluid-Solid Coupling

Abstract: The interaction between abrasive waterjet and target is studied by computational fluid dynamics (CFD) and finite element method (FEM). The flow field inside and outside abrasive waterjet (AWJ) nozzle is obtained by CFD software. Then the pressure distribution of the fluid on the target is plotted, which is in well agreement with the force distribution of the AWJ impacting on the target and leads to the material deformation. The interaction between the AWJ and target and the fluid-solid coupling is happened. The cloud figure of the target’s deformation and stress are obtained by FEM software. The AWJ parameters such as the flow velocity, off-set and abrasive volume factor have a great effect on the material deformation and the stress distribution. The study results provide a new method to study abrasive water jet machine mechanism and help to optimize process parameters.

Abstract: This article make numerical simulation and analysis to hydraulic torque converter model base on finite element. The model is build by CATIA (model software). Application of ADINA (finite element software) calculate and analysis the single fluid-passage in pump impeller, then use ANSYS Workbench (finite element software) analysis structural strength and modal of hydraulic torque converter. Results showed that the calculation is accordant with hydraulic torque converter working situation that proved the feasibility and the effectiveness of the numerical simulation. So numerical simulation can provide certain theoretical reference for the design of the hydraulic torque converter.

Abstract: This paper does unidirectional fluid-solid coupling calculation on the runner strength under three designed head loading conditions of a certain Francis turbine in the north-eastern China. The water pressure on the blade in the flow fields of different operating conditions is calculated by means of CFD software CFX. With the help of ansys workbench, the water pressure is loaded to the blade as structural load to conclude the static stress distribution and deformation of the runner under different operating conditions. The results show that the maximum static stress increases with the rise of the flow and appears near the influent side of the blade connected to the runner crown; the maximum deformation increases with the rise of the flow and appears on the band. The results provides effective basis for the structural design and safe operation of the Francis turbine.

Abstract: Horizontal well hydraulic fracture construction technology has already become the main development means of low permeability reservoir, and the crack initiation pressure is a key factor in fracture construction. Taking ABAQUS as the platform, combined with rock mechanics, elastic mechanics, fracture mechanics, damage mechanics and fluid-solid coupling theory, to establish horizontal well mechanical model, crack initiation law of horizontal well under different conditions were obtained by using finite element method. According to the horizontal well fracture tested data in Daqing peripheral oil fields, the crack initiation pressure and numerical simulation results are in good agreement, it shows that the numerical simulation method is reasonable, then analyze influence factor of crack initiation pressure on the basis.

Abstract: Water inrush is one of the main types of coal mine water disaster. Based on fluid-solid coupling theory, the confined water inrush numerical model is performed using FLAC3D program and similar simulation experiment, and the floor damage field and confined water vector field are simulated. The results show that, in the coupling action of mining stress and pressure of confined water, the mining floor was divided into four zones, namely the mining damage zone, effective confining protection zone, confined water soil-fluid coupling lifting zone, original confined water lifting zone. Confined water-conductive zone with the periodic roof pressure fluctuate, at each pressure and flowing zone height reaches the maximum, rise with height remained unchanged, the distribution shape of a "wave", water inrush is the results of effective connectivity of mining damage zone and Confined water-conductive zone, plate thickness of water-resisting layer exists or not, waterproof performance and the pressure of confined water inrush size is the key

Abstract: In this paper, the vibration characteristics of plate and stiffened plate in the flow field are calculated by employing fluid-solid coupling method. The wet-frequency and wet-mode numerical computing results are analyzed. The influence of boundary condition, edge length ratio and depth of water on wet mode and wet frequency are studied. A mixed finite element-boundary element method is adopted in the numerical calculation, which makes the added water mass matrix calculation be limited to the liquid-solid interface. Thereby, the calculated amount is significantly reduced and the calculation efficiency is increased.

Abstract: The microwave resonant cavity is the sensor of wetness measurement in medium perturbation method. Local eddy current and viscous dissipation of stream will cause the temperature difference of cavity, which led to the shift of resonant frequency affecting the stability of sensor. This paper calculates the temperature distribution of cavity under conditions that varieties of steam parameters and velocity of flow by flow-solid coupling method. The thermal deformation of different conditions of cavity is calculated. The influence of thermal deformation to the resonance frequency of resonant cavity is analyzed, according to the average value of node deformation of the cavity effective surface. The results show that the average temperature of cavity and thermal deformation increase with the steam parameter increase and the offset value of resonance frequency increases. The wetness measurement scheme of wet steam on the turbine exhaust needs to improve to reduce the effect of cavity body deformation.

Abstract: Joints and fissures have a strong impact on the stability of engineering rock mass. In this paper, a self-improved analysis program of FLAC^3D is adopted to study problems in fluid-solid coupling field. Then, by simulating the excavation process of a slope under the effect of fissure water pressure, the crack initiation and propagation in engineering rock mass reappears. Besides, the numerical simulation results are decent and effective, which can provide some references for engineering application.

Abstract: Based on the fluid-solid coupling theory, The fractured rock mass was described as a continuous porous medium, and consider the rock mass permeability coefficient has a relationship with the stress and strain. The dynamic change of permeability coefficient was achieved using the multi-physics coupling analysis software COMSOL, and found that the stress and strain of surrounding rocks changes a lot due to mining. The maximum stress and strain in the mudstone area reaches 2-3 times of the original one, which happened at the immediate roof of mined-out area. According to the analysis of seepage field, mining does not destroy water resistance of floor aquifer. Mining fissures do not connect limestone aquifers, and water in the limestone is less likely to flow into stop to cause damage.