443 results about "Fluid solid coupling" patented technology

The invention discloses an optimization design method of fibre enhanced composite material marine propeller blades, which relates to an optimization design method of propeller blades and aims at solving the problem of imperfect design method of the fibre enhanced composite material marine propeller blades. On the basis of offsets data of the original high-speed metal propeller blades, the method is calculated by using a fluid-solid coupling method combining with the implementation of predeformation strategy, a blade structure is composed by mixed fibre composite materials, the surface of a blade adopts fibre glass enhanced composite material, the interior of the blade adopts the mixture of carbon fiber and Kelvar fiber enhanced composite material, and the specific mixed paving mode and the mixing ratio are determined according to the hydro elastic design result of a fibre enhanced composite material marine propeller. The optimization design method is used for designing the propeller blades.

The invention belongs to the technical field of unconventional oil gas production increasing transformation and particularly, relates to a shale gas horizontal well refracturing productivity calculation method. The method comprises the following steps of: by using a shale reservoir as an elastic material which is small in deformation, establishing a stress-strain model and a reservoir physical property parameter dynamic model; establishing a continuity equation in kerogen and an inorganic substance; respectively carrying out numerical solution on an established solid deformation control equation and shale gas multiscale seepage equation; bringing geological parameters, physical property parameters and primary fracturing design parameters of a shale gas well reservoir into a shale gas fluid-solid coupling numerical model, and recording a pressure field and hydraulic fracture flow conductivity of the reservoir; and bringing refracturing design parameters into the shale gas fluid-solid coupling numerical model, and calculating productivity of a shale gas well after refracturing. According to the method disclosed by the invention, seepage characteristics and stress-pressure field dynamic variations of the shale reservoir are considered, productivity and a recovery ratio of the shale reservoir after refracturing are predicted, and shale gas horizontal well refracturing optimizationdesign is guided.

The invention discloses a time domain bidirectional iteration-based turbine vane flutter stress forecasting method. The method is characterized in that: a set of bidirectional iteration method for a time domain is designed by taking a vane and a surrounding flow field thereof as a three-dimensional fluid solid coupling system, and the flutter stress of the vane is obtained by alternately solving vane deformation and unsteady flow field. The method comprises the following steps of: setting a structural calculation module, a fluid calculation module, a data conversion module, a flutter stress output module, an initial value calculation module and a bidirectional iteration module in a computer; acquiring static vane deformation and steady flow field serving as an initial value by nonlinear iteration; alternately calling the structural calculation module and the fluid calculation module to propel the whole system on time; transmitting fluid solid boundary information through the data conversion module; and outputting the flutter stress on time history. The method realizes integrated calculation of the vane and the flow field, takes the nonlinearity of the coupling system into consideration, and can allow the observation of the whole flutter development process and forecast the flutter stress of the vane.

The invention discloses a method for simulating offshore oilfield micro fracturing injection increase crack propagation on the basis of fluid-solid-heat coupling theory. The method comprises the following steps that geological characteristic parameters are obtained on the basis of offshore micro fracturing well geological data; a hydraulic crack propagation model is built, and fluid pressure and filter loss in a crack are obtained; on the basis of a reservoir matrix model, dynamically changing pore pressure in a reservoir is worked out; on the basis of elastic mechanics and permeation fluid mechanics, a pore elastic deformation relation between fluid and rock is built, that is to say, a fluid-solid coupling model is built, and by means of the calculated pore pressure, rock strain caused bythe fluid can be obtained; a heat effect relation between the temperature and the rock is built, a strain, porosity, permeability and temperature fluid-solid-heat coupling model is built, the permeability and porosity after coupling change are obtained, the pore pressure after three-field coupling change is obtained, the changed pore pressure reacts on a Darcy filtration model, and the crack extension dynamic of the next moment is obtained. According to construction and geological parameters, the dynamic extension situation of the hydraulic crack and real-time change situation of the reservoir parameters in the offshore micro fracturing well long-term injection increase process can be predicted according to the construction and geological parameters.

The invention discloses a prediction method for saturated and unsaturated permeability coefficients of deformed soil based on a fractal theory. The prediction method comprises the following steps: taking a soil-water characteristic curve of soil samples before deformation as a reference state, using a fractal model of the oil-water characteristic curve and fitting to obtain a fractal dimension D0 and an air entry value Psi a0 before the deformation, making the fractal dimension unchanged before and after the deformation, combining with a prediction model of the deformed air entry value to obtain a deformed air entry value Psi a, combining the deformed fractal dimension D0 and air entry value Psi a through a saturated/unsaturated relative permeability coefficient model, predicting the saturated permeability coefficient and an unsaturated relative permeability coefficient of the deformed soil, and multiplying the saturated permeability coefficient and the unsaturated relative permeability coefficient to obtain the unsaturated permeability coefficient. The prediction method for the saturated and unsaturated permeability coefficients of the deformed soil based on the fractal theory disclosed by the invention overcomes the defects that the prediction of the permeability coefficients is empirically based, thereby lacking theoretical support and having complicated calculation, and has the advantages of having extremely important values in seepage theories and fluid-solid coupling research and engineering application of saturated/unsaturated soil.

The invention provides a method for estimating a reverse twisting process of a fan blade of a gas turbine, and aims to solve the problem that the conventional gas turbine fan blade reverse twisting design method is incomplete. According to the method, a cold state blade profile can be finally obtained by steps of performing analysis software (ANSYS) centrifugal force static deformation analysis on a thermal state blade profile, forecasting the cold state blade profile, then performing ANSYS centrifugal force static deformation analysis on the forecast cold state blade profile, transitioning a virtual thermal state blade profile, correcting a solid and liquid grid, performing aerodynamic force deformation fluid-solid coupling analysis and the like. The method has great significance for implementing consistency between the forecast thermal state blade profile and an actual working state blade profile of the blade under each pneumatic working condition and researching a method for precisely estimating the reverse twisting process of the fan blade of the gas turbine; and particularly, the method has important engineering application value in developing transonic speed fans with large bypass ratios.

The invention discloses a design method for property parameters of anti-collapse drilling fluid for fractured formations. According to sequence, the design method includes the following steps: core samples are prepared; four of the core samples are chosen for a triaxial compression test and an acoustic emission test, and the crustal stress of a formation owning the core samples is determined; two of the core samples are chosen for the triaxial compression test, and the cohesion and internal friction angle of the weak planes of the rocks are tested; eight of the core samples are chosen to be put into the drilling fluid, the triaxial compression test is carried out after the core samples are soaked for different times, and the cohesion and internal friction angle of the weak planes of the rocks are tested; the cohesion and internal friction angle of the weak planes of the rocks are respectively linearly fitted to soaking times; the fluid-solid coupling theory is utilized to create a fractured formation well surrounding rock stress distribution model; the elastic mechanics coordinate transformation theory is utilized to create a fractured formation weak plane destruction model; a relation chart between the property parameters of the drilling fluid is determined. The design method disclosed by the invention can quantitatively optimize the key property parameters of the drilling fluid according the requirement of a site for well wall stability.

The invention discloses a method for forecasting a weak plane formation collapse pressure equal yield density window. The method sequentially includes the steps: dividing a weak plane formation into a compact section and a crack section according to characteristics of the weak plane formation; testing the strength of a rock body and the strength of a weak plane of a rock by the aid of the triaxial compression test of the rock; inverting stress distribution and pore pressure distribution of surrounding rocks of a compact formation well by the aid of a fluid-solid coupling model, and determining the lower limit of the collapse pressure equal yield density of a compact formation according to Mohr-coulomb failure criteria; analyzing the failure state of the surrounding rocks of the weak plane formation well according to the rock weak plane failure criteria, and determining the lower limit and the upper limit of the collapse pressure equal yield density window of a crack formation; building a weak plane formation collapse pressure equal yield density window calculation model, substituting parameter values into the model and then determining the weak plane formation collapse pressure equal yield density window. The weak plane formation collapse pressure equal yield density window can be forecasted before drilling, so that drilling fluid density is reasonably selected, and wellbore instability is effectively stopped.

The invention discloses a bidirectional fluid-solid coupling three-dimensional numerical simulation method for a high-speed pantograph. The method comprises the following steps: firstly, constructinggeometric models of a fluid domain and a solid domain of the high-speed pantograph; secondly, according to the model constructed in the first step, conducting grid division on a pantograph fluid domain and a pantograph solid domain respectively; then setting material parameters, initial conditions and boundary conditions of a fluid domain and a solid domain; adding a pantograph fluid-solid coupling data exchange surface, and performing bidirectional fluid-solid coupling numerical analysis of the high-speed pantograph; and finally, obtaining a pantograph displacement cloud picture and a stresscloud picture according to a kinetic analysis result in the step 4, and obtaining an aerodynamic time-history curve of each part of the pantograph according to a hydrodynamic analysis result. On the basis of the bidirectional fluid-solid coupling theoretical model, the change of the operation posture of the pantograph under the aerodynamic force effect is considered, aerodynamic characteristic calculation and stress deformation research of the pantograph under the high-speed airflow effect are achieved through numerical simulation, and the nature of the aerodynamic characteristics of the pantograph can be reflected more objectively.

The invention discloses a numerical analysis method applied to a leaking and channeling mechanism and a prevention and control method of an injection fluid. The method is used for carrying out research based on the fluid-solid coupling theory by virtue of a method with combination of indoor test, numerical calculation and field detection. By virtue of the method, typical mudstone is selected for carrying out indoor test under different water ratios and building an inversion model of stress and deformation of a point-changeable stratum of an inversion sleeve of deformation data of a sleeve. On account of a typical injection-production scheme, the accurate positions of leakage, interzone and flowing along fault are judged and optimized by comparing the numerical simulation and the field detection; finally, a reasonable injection-production scheme and a reasonable measure for preventing serious loss of injection water are provided; and the method has important application values of improving the injection-production effect of the oil field and improving the final recovery rate and the whole development level of the oil field.

The invention discloses a fault analog simulation material used for a fluid-solid coupling model test, which comprises components in parts by weight as follows: 1 part of quartz sand, 0.05-0.25 part of talcum powder, 0.05-0.15 part of gypsum powder, 0.08-0.2 part of Vaseline and 0.1-0.2 part of water. The material adopts gypsum as a cementing agent, so as to achieve simulation for fault fluid-solid coupling characteristics; the talcum powder and the quartz sand are adopted as conditioning agents to regulate the weight of the material; and the Vaseline is adopted as a water resistant agent to regulate permeability of the material, simultaneously adopted as a plastic cementing agent of the material, and used for simulating the fault fluid-solid coupling characteristics under different permeability conditions, and real-time comparison with surrounding rock fluid-solid coupling characteristics in the same experiment is achieved. The fault analog simulation material in the fluid-solid coupling model test disclosed by the invention can regulate the strength and the permeability of the material within a larger range, and simulate various types of faults at various levels of intensity.

The invention belongs to the technical field of medical imaging, and particularly relates to a method for predicting the growth of coronary atherosclerotic plaque. The method comprises the steps thatIVUS images and OCT images of at least two moments are segmented respectively, then the segmented IVUS images and OCT images are fused, a three-dimensional multi-modality fluid-solid coupling model with cyclic bending is established according to a fused contour, a mechanical result of the model is calculated, risk factors of mechanics and morphology are extracted in combination with a morphological result, a plaque growth indicator is given, and the growth of the plaque is predicted by using a machine learning method, thereby providing an accurate and reliable method for predicting the growthof coronary plaque. The method for predicting the growth of the coronary atherosclerotic plaque provides the possibility of clinical application for plaque growth prediction.

The invention discloses a multi-physical field coupling simulation method and a multi-physical field coupling simulation system for a submarine high-pressure blow-off pipeline system. The method comprises the steps of establishing a three-dimensional geometrical model of a high-pressure blow-off system pipeline; performing finite element mesh division and boundary condition setting on the three-dimensional geometrical model of the high pressure blow-off system pipeline; performing fluid mechanic simulation calculation to obtain flow field characteristics in the high-pressure blow-off system pipeline and flow-induced noise characteristics in the blow-off system; performing simulation analysis on a fluid-solid coupling problem of the high-pressure blow-off system pipeline based on a multi-physical field fluid-solid coupling simulation calculation method; performing transient acoustic boundary element simulation calculation by use of an acoustic simulation calculation method based on a fluid-solid coupling simulation calculation result; and performing qualitative and quantitative analysis on flow field noises, flow-induced noises and vibration noises of the system pipeline and a watertank based on the multi-physical field fluid-solid-sound coupling simulation method. Through the multi-physical field coupling simulation means, the invention provides a noise prediction system for the submarine high-pressure blow-off pipeline system.

The invention discloses a self-adaptive mesh control method applicable to fluid-solid coupling numerical simulation in a paradrop process. Self-adaptive tracking of a local flow field around a parachute in movement is carried out by means of free transformation of ALE (arbitrary Lagrangian Eulerian) meshes, and consequently the defect of limits on paradrop motion range by spatially-fixed flow field meshes in existing numerical simulation method can be overcome, calculation amount is effectively decreased, and quickness and high precision in fluid-solid coupling numerical simulation of the large-range paradrop motion process are realized.

A power transmission line wind vibration control method based on power transmission line iron tower and lead or ground wire integrated system model calculation and multi-dimensional random gust field simulation includes the steps: firstly, generating a wind load time history sample by the aid of harmonic synthesis to simulate a wind field based on a multi-dimensional random vibration theory; secondly, establishing a dynamic model of an integrated system of a tower, lead or ground wire and wind vibration control device, analyzing the initial state of a lead or a ground wire and setting boundary conditions of the model; thirdly, converting wind load into wind pressure, loading a power transmission tower and line system and calculating time history of axial stress and displacement of an iron tower rod by the aid of simulation software; and fourthly, analyzing and judging wind vibration strength and wind vibration suppression effects and improving control effects by the aid of an optimization scheme. On the basis of rigid-flexible dynamic coupling among a power transmission line tower, the lead and the ground wire and fluid-solid coupling between a random gust wind field and a tower and lead or ground wire system structure, the determined wind vibration control method has better implementation effects.

The invention relates to a visual reaction kettle and a visualized experimental system and method for replacing natural gas hydrate. The reaction kettle used by the system comprises a barrel, a front flange, a rear flange and glass; the front flange, the rear flange and the barrel are each of a hollow structure, the glass is embedded on the hollow structure of the front flange and the hollow structure of the rear flange respectively, and the front flange, the rear flange and the glass are used for sealing the barrel; the barrel is provided with multiple connectors; the system comprises a sampling tank, a vacuum pump, a first natural gas bottle, a carbon dioxide gas bottle, a second natural gas bottle, an environmental climate case, a beaker, a sensor, an image acquisition device and a data acquiring and processing device. By means of the experimental system, the process of replacing the natural gas hydrate with carbon dioxide at different phase states can be carried out, macroscopic thermodynamic and dynamic data in the replacing process is obtained, and meanwhile the dynamic characteristics, the heat-fluid-solid coupling phenomenon and the hydrate form change in the replacing process are recorded; the visual reaction kettle and the visualized experimental system and method for replacing the natural gas hydrate can be used for observing the natural gas hydrate generation phenomenon.

The invention discloses a multi-field coupling transient numerical method for hypersonic flow-heat transfer and structural response. The method comprises the following steps of: determining wall temperature and displacement boundary condition according to structure, performing data exchange at a fluid-solid coupling interface, and obtaining the current temperature and displacement boundary condition; simultaneously solving coupled solution format of each preset conservation equation to obtain the current heat flux and pressure; performing data exchange at the fluid-solid coupling interface to obtain the boundary condition of a solid region; according to the boundary condition of the solid region, solving out the wall temperature and structure displacement through a thermal mechanical unity coupling method; and executing the steps above repeatedly until meeting a preset stop condition. Using the method provided by the invention, multi-field coupling calculation where a hypersonic non-equilibrium flow solver and a structural thermal/mechanical unity coupling solver are coupled is realized, prediction on pneumatic thermodynamic environment and structural thermodynamic response of a hypersonic aircraft meets physical reality better, and calculation precision can be guaranteed.

The invention relates to a test device for research on vibration of construction in a flow field, and specifically to a test device with controllable vibrational degrees of freedom for vortex-induced vibration of cylinders. The test device comprises elastic supports arranged on a pedestal and a model pipeline arranged on the elastic supports, wherein, the elastic support comprises a rack and a pipe clamp for installing the model pipeline, a spring core bar is provided between the rack and the pipe clamp, a spring is sleeved on the spring core bar, chutes are provided on the rack, slide blocks are provided in the chutes, and the slide blocks are connected with the pipe clamp through the spring core bar. According to the invention, vibration at two directions can be controlled respectively, which enables the problem that fluid-solid coupling can not be tested in research on vortex-induced vibration to be overcome.

The invention discloses a shale gas reservoir fluid-solid coupling multi-scale numerical simulation method. The method comprises the following steps: obtaining spatial distribution and physical property parameters of organic matters and inorganic matters, constructing a physical model of a micro-scale shale matrix, solving a micro-scale seepage auxiliary equation and a mechanical auxiliary equation, and calculating equivalent seepage and mechanical parameters of the shale matrix core scale; acquiring a natural fracture distribution situation, constructing a rock core scale physical model containing a shale matrix and natural fractures, solving a seepage auxiliary equation and a mechanical auxiliary equation of the rock core scale, and calculating equivalent seepage and mechanical parameters of a shale gas reservoir macro-scale; on the basis, simulating a hydraulic fracture by adopting an embedded discrete fracture model, and establishing a shale gas reservoir macroscopic fluid-solid coupling model; and finally, based on the structured grid, solving the shale gas reservoir fluid-solid coupling model by adopting a mixed numerical discretization method combining simulated finite difference and extended finite elements so as to realize shale gas reservoir fluid-solid coupling numerical simulation with high simulation precision and small calculated amount.

The invention discloses a fluid-solid coupling similar material for a model test. The material consists of the following raw materials in part by weight: 1 part of standard sand, 0.05 to 0.15 part of barite powder, 0.05 to 0.15 part of talcpowder, 0.05 to 0.125 part of cement, 0.04 to 0.12 part of vaseline, 0 to 0.15 part of silicone oil and 0.05 to 0.1 part of mixing water. Hydraulic cement and non-hydrophilic vaseline are taken as cementing agents in the material, so that the problem that the similar material is softened and disintegrated when meeting water is solved, and the strength and elastic modulus of the material can be adjusted in a wide range; the silicone oil is taken as an adjuster, so that the water physical indexes such as permeability and the like of the material can be adjusted under the condition that the mechanical indexes of the material are basically not influenced, and the physical and mechanical properties and water physical properties of the material can meet the test requirement; and compared with previous research, the invention has the advantages that: the intercoupling effect of a rock body and water is truly simulated, and the obtained geomechanical similar model test research result is more accurate.

The invention discloses a fluid-solid coupling coal petrography shear-seepage test shearing and sliding combined shearing box which comprises an upper box body and a lower box body which are fixedly connected with each other, wherein cavities for containing test pieces are formed in the upper box body and the lower box body; a first flange and a second flange are respectively arranged on the front side and the rear side of the upper box body; a third flange and a fourth flange are respectively arranged on the front side and the rear side of the lower box body; a second rolling way and a second rolling way are respectively arranged on two sides of the first flange and the two sides of the second flange of the upper box body; clamping plates are arranged on the second rolling way and the third rolling way; a fourth rolling way and a fifth rolling way are respectively arranged on the inner sides of the third flange and the fourth flange of the lower box body; four threaded holes are rectangularly formed in the lower box body; waist-shaped through holes are formed in positions, which correspond to the threaded holes, on the upper box body; bolts penetrate through the clamping plates and the waist-shaped through holes and are matched with the threaded holes. The fluid-solid coupling coal petrography shear-seepage test shearing and sliding combined shearing box can simulate a real actual working condition, so that the test precision can be improved.

The invention discloses an elastic vane propeller flow noise prediction method. The method comprises the following steps: building a full-size model for a propeller and a fluid domain to be analyzed, wherein the model comprises a rotating domain which rotates along with the propeller and a static domain which does not rotate; meshing the full-size model and setting a noise sampling point; setting solving parameter of a flow field and a sound field for the meshed full-size model; updating the dynamic mesh for the full-size model; setting the material property for the solid part of the propeller; conducting grid partitioning and coupling surface parameters; setting fluid-solid coupled computing process parameters and fluid-solid coupled control equations; wherein, tau is the stress, n is the normal vector, d is displacement, and the subscripts f and s refer to the fluid and the solid respectively; conducting fluid-solid coupling until the algorithm converges; obtaining flow field data at the monitoring point; calculating the pressure level of the monitoring point according to the FW-H equation; obtaining a power spectral density curve of the sound field according to the fast Fourier transforming FFT function.

The invention provides a CCPDI-IMPM method for large deformation analysis pf a saturated porous medium based on a u-p control equation of a generalized Biot theory and a convective particle domain interpolation technology, and the method comprises saturated porous medium large deformation consolidation process analysis and saturated porous medium large deformation dynamic process analysis. According to the method, an implicit time integral strategy is adopted to overcome the defect that a traditional explicit material point method is limited by a critical time step length, and particularly, the calculation efficiency is remarkably improved when a quasi-static problem is solved; and the grid boundary smooth interpolation advantage of the CPDI and the Euler-Lagrangian description advantage of the implicit substance point method are combined, so that compared with the traditional FEM, the calculation performance is more stable when large deformation and extremely large deformation are processed. The invention further provides a method for expanding the substance penalty factor, and the method is used for processing the boundary condition of the fluid-solid coupling system more simplyand accurately.