9 results about "Phase model" patented technology

This invention provides a method and system for predicting the combined wear and fatigue failure of turbine runner blades, relating to the field of hydropower equipment operation and maintenance technology. The method includes: establishing a fluid computational domain model and mesh generation; constructing a flow field based on single-phase flow characteristics; constructing a two-phase flow system using a discrete phase model; constructing a material wear model based on the characteristics of suspended matter passing through the machine; obtaining a geometrically varying wear prediction model and calculating the model; calculating the fluid-structure interaction strength characteristics of the initial structural field, and based on the calculation results, calculating the fatigue characteristics of the initial structural field; reconstructing the flow channel geometrically varying model based on fatigue characteristic data, and calculating the flow and fatigue characteristics during the reconstruction process; and evaluating the fatigue failure prediction of the runner under the influence of wear. This invention utilizes dynamic mesh smoothing technology to achieve real-time reconstruction of the geometric model and iterative coupling of the flow field and structural field during the wear process, improving the accuracy and scientific rigor of failure prediction.

The application relates to a UAV array dynamic angle of arrival estimation method and system, which comprises the following steps: S1, acquiring array snapshot data after reference channel auxiliary synchronization and waveform compensation; S2, establishing a parameterized space-time coupling phase model in a short coherence processing interval; S3, based on the array snapshot data, obtaining a single-channel input sequence through beam forming, and estimating a radial parameter pair by using time domain atom matching filtering; S4, based on the radial parameter pair, performing common time phase compensation on the array snapshot data to obtain a compensated snapshot matrix; S5, performing two-dimensional correlation calculation by using a space-time steering atom to estimate an angle parameter pair; S6, constructing a complete space-time dictionary atom, and estimating a complex amplitude by using a least square criterion; and S7, performing successive interference cancellation to update a residual error. Compared with the prior art, the application has the advantages of keeping low signal-to-noise ratio coherence gain and significantly reducing calculation complexity.

The application discloses a kind of coupling molecular dynamics first principle's gas cooled reactor cladding surface particle adsorption calculation method, steps are as follows: (1) based on computational fluid dynamics and particle discrete phase model establishes numerical simulation framework, including cladding, break, flow channel modeling, grid drawing, boundary condition setting;(2) according to the first principle of molecular dynamics, the binding surface energy of fission product molecules released into the gas gap and the cladding material molecular base is calculated;(3) establish the particle deposition model including particle's own attribute, effective modulus, relaxation time and surface energy;(4) the binding surface energy is implanted into the particle deposition model, and the particle deposition model is used as the wall boundary, and the gas-solid two-way coupling calculation of particle deposition is carried out.The method solves the problem that traditional macroscopic model depends on empirical parameters, realizes high-precision simulation based on physical mechanism, reveals the mechanism of micro-interface properties on macroscopic deposition behavior, and predicts complex deposition morphology.

This invention discloses a numerical simulation method for chloride ion diffusion in recycled aggregate concrete based on a five-phase random aggregate model, belonging to the field of numerical simulation technology for building material durability. This invention solves the problems of low modeling accuracy of the microstructure of recycled concrete, fragmented modeling and assignment processes, and the inability to dynamically optimize in existing technologies. The technical solution includes: parametrically defining a five-phase model consisting of a core-old ITZ-old mortar-new ITZ-new mortar; using a piecewise integration method to achieve precise control of aggregate gradation; automatically constructing multi-layered annular geometry through Boolean operations; synchronously generating explicit selection sets for each phase; performing transient simulation of chloride ion diffusion, identifying high-concentration gradient regions based on error analysis; automatically backtracking and dynamically adjusting the selection set partitioning, assigning diffusion coefficients based on local diffusion characteristics, and performing adaptive mesh refinement; and continuing subsequent solving. This invention achieves an intelligent closed loop of "modeling-solving-refinement-resolving," significantly improving simulation accuracy and efficiency, and providing an efficient and accurate numerical tool for the durability assessment of recycled concrete.

A method for predicting cavitation intensity within the runner of a large-scale hydro-turbine unit includes the following steps: simplifying the gas-liquid two-phase flow within the entire runner channel under typical operating conditions; extracting a complete three-dimensional geometric model of the runner channel, generating a computational mesh, and verifying mesh independence; configuring the solver and computational mode, enabling the multiphase flow model and the turbulence model, and setting boundary conditions, flow field initialization methods, and computational convergence criteria; extracting impurity parameters and arranging discrete phase particles representing impurities in the water; simulating the movement of particles within the runner channel using the discrete phase model to obtain the particle distribution and mass concentration within the channel; calculating the partial pressure of insoluble gases to quantitatively characterize the influence of water quality; calculating the corrected vaporization pressure; obtaining the cavitation occurrence location within the channel and quantitatively evaluating the cavitation intensity; and comparing the cavitation intensity prediction results considering and not considering water quality. This application can improve the prediction accuracy of hydro-turbine cavitation intensity.

This invention discloses a simulation calculation method for macro- and micro-scale coupled pollution at coal material induced airflow transfer points, comprising the following steps: S1: Constructing a three-dimensional model of an open underground transfer point and a flow field calculation grid; S2: Establishing a macro- and micro-scale separation strategy for solid materials; S3: Calculating macroscopic coal flow motion and spatial porosity based on the discrete element method; S4: Calculating fine dust diffusion based on a fluid dynamics discrete phase model; S5: Performing asynchronous coupled calculations of fluid and discrete element methods, which can avoid simulation result distortion and the problem of coupled simulation easily leading to grids exceeding 100 million and calculation divergence.

The application belongs to the technical field of aero-engine icing simulation, and discloses a kind of ice crystal melting icing whole process simulation calculation method in aero-engine compressor passage, first, the fluid domain model of compressor is established and initial flow field is obtained;Subsequently, the movement, impact and phase change process of ice crystal are simulated by combining discrete phase model and user-defined function;Further, the ice accumulation is calculated based on the icing thermodynamic model, and the dynamic mesh technology is driven to update the grid node position of blade surface in real time, and the icing topography is reconstructed;Finally, the reconstructed ice model is calculated for flow field, and the aerodynamic performance loss caused by icing is analyzed.The application realizes the whole process dynamic coupling simulation from ice crystal transport, ice growth to aerodynamic influence evaluation, and provides accurate and effective numerical analysis means for compressor ice crystal icing risk assessment.

This invention discloses a method for calculating the interfacial tension of oil and water within nanopores, belonging to the field of molecular simulation and interface physics. The method includes: constructing an oil-water two-phase model in a silica nanochannel; applying equal and opposite external forces to the oil and water phases to perform all-atom molecular dynamics simulation; after the simulation, identifying interface atoms using a sliding window method based on atomic trajectory data, and combining quadratic curve fitting and effective frame screening to reconstruct the geometry of the oil-water interface with high precision; finally, calculating the interfacial tension according to the mechanical equilibrium formula, where θ is determined by the tangent of the fitted curve at the nearest neighbor of the wall. This invention avoids the low resolution problem of traditional density profiling methods at the nanoscale, significantly improving the accuracy of interface positioning and the reliability of tension calculation, and is suitable for quantitative research on nano-percolation behavior in unconventional oil and gas resources.

The application discloses a simulation calculation method for macro-micro coupling pollution of a coal mine material induced airflow transfer point, and comprises the following steps: S1, constructing an underground open transfer point three-dimensional model and a flow field calculation grid; S2, establishing a macro-micro scale separation strategy of a solid phase material; S3, calculating macroscopic coal flow movement and spatial porosity based on a discrete element method; S4, calculating micro-fine dust diffusion based on a fluid mechanics discrete phase model; and S5, performing asynchronous coupling calculation of a fluid and a discrete element, so that the problems of simulation result distortion and grid over one hundred million and calculation divergence caused by coupling simulation can be avoided.