40 results about "Material point method" patented technology

The disclosure provides an approach for simulating and rendering granular materials. A simulation application generates video frames depicting a granular material phenomenon using a strain based elasto-plastic constitutive model integrated with a hybrid Eulerian / Lagrangian material point method (MPM). The elasto-plastic constitutive model includes physical equation(s) which dictate forces that affect the granular material during the simulation. In particular, the constitutive model may include user-controllable parameters defining threshold(s) to start plastic deformation, as well as a hardening parameter which controls how fast the granular material packs under compression. The MPM is a procedure in which particles of the granular material and a background grid are coupled, with the grid being used to assist in computing forces dictated by the physical equation(s) of the elasto-plastic constitutive model. In one configuration, the grid may further be rendered with volumetric rendering to generate video frames depicting the granular material.

A method for approximating an optimal power flow of a smart electric power grid includes providing a cost function that models a smart electric power grid having buses connected by branches, deriving a set of linear equations that minimize the cost function subject to constraints from an expression of an extremum of the cost function with respect to all arguments, reducing a dimension of the linear equations by solving for a subset of the linear equations, re-organizing the reduced dimension linear equations into primal and dual parts, and decomposing the re-organized reduced dimensional linear equations into two systems of block matrix equations which can be solved by a series of back substitutions. A solution of the two systems of block matrix equations yields conditions for a lowest cost per kilowatthour delivered through the smart electric power grid.

The disclosure provides an approach for reducing information loss when transferring from particles to grid and vice versa in a hybrid Lagrangian / Eulerian simulation, while also preserving stability. In one aspect, referred to as the rigid particle-in-cell (RPIC) method, a simulation application stores a sampling of local angular momentum for each particle, helping to preserve the angular momentum that would otherwise be lost in the transfer from grid to particles. In another aspect that is more generally applicable and referred to herein as the rigid and shearing particle-in-cell (RSPIC) method, the simulation application stores, for each particle, a matrix with rotational and shearing information. The RSPIC method effectively reduces dissipation, preserves angular momentum exactly, and prevents instabilities. Further, the RSPIC method is applicable to both incompressible liquids and material point method (MPM) simulations of materials such as solids.

A computer system and method of simulating the behavior of an oil and gas reservoir including changes in the margins of frangible solids. A system of equations including state equations such as momentum, and conservation laws such as mass conservation and volume fraction continuity, are defined and discretized for at least two phases in a modeled volume, one of which corresponds to frangible material. A material point model technique for numerically solving the system of discretized equations, to derive fluid flow at each of a plurality of mesh nodes in the modeled volume, and the velocity of at each of a plurality of particles representing the frangible material in the modeled volume. A time-splitting technique improves the computational efficiency of the simulation while maintaining accuracy on the deformation scale. The method can be applied to derive accurate upscaled model equations for larger volume scale simulations.

The invention relates to a material sorting method, which belongs to the technical field of intelligent logistics. This sorting method starts from the sorting order of the material (obtainable according to the demand list), decomposes the sorting order into multiple sorting tasks, and sorts the sorting tasks so that the sorting can be performed more efficiently. It should be pointed out that the present invention is provided with an indicator light corresponding to the placement position of the picking box on the sorting rack. When the sorting task is performed, the corresponding indicator light is on to prompt the sorting personnel to perform accurate feeding, which greatly simplifies The working process improves the sorting accuracy and efficiency.

The disclosure provides an approach for reducing information loss when transferring from particles to grid and vice versa in a hybrid Lagrangian / Eulerian simulation, while also preserving stability. In one aspect, referred to as the rigid particle-in-cell (RPIC) method, a simulation application stores a sampling of local angular momentum for each particle, helping to preserve the angular momentum that would otherwise be lost in the transfer from grid to particles. In another aspect that is more generally applicable and referred to herein as the rigid and shearing particle-in-cell (RSPIC) method, the simulation application stores, for each particle, a matrix with rotational and shearing information. The RSPIC method effectively reduces dissipation, preserves angular momentum exactly, and prevents instabilities. Further, the RSPIC method is applicable to both incompressible liquids and material point method (MPM) simulations of materials such as solids.

The disclosure provides an approach for simulating and rendering granular materials. A simulation application generates video frames depicting a granular material phenomenon using a strain based elasto-plastic constitutive model integrated with a hybrid Eulerian / Lagrangian material point method (MPM). The elasto-plastic constitutive model includes physical equation(s) which dictate forces that affect the granular material during the simulation. In particular, the constitutive model may include user-controllable parameters defining threshold(s) to start plastic deformation, as well as a hardening parameter which controls how fast the granular material packs under compression. The MPM is a procedure in which particles of the granular material and a background grid are coupled, with the grid being used to assist in computing forces dictated by the physical equation(s) of the elasto-plastic constitutive model. In one configuration, the grid may further be rendered with volumetric rendering to generate video frames depicting the granular material.

The disclosure provides an approach for simulating and rendering materials across different states and undergoing phase transitions. In one configuration, a simulation application generates video frames depicting a material phenomenon using an augmented material point method (MPM). Traditional MPM does not handle incompressible materials such as fluids. Techniques disclosed herein augment the MPM with a Chorin-style projection technique to enable simulation of arbitrarily incompressible materials. In one configuration, this is achieved with a marker-and-cell (MAC) grid based MPM solver, a splitting of stress used in the simulation into elastic and dilational parts, a projection-like implicit treatment of the Eulerian evolution of the dilational part of the stress, and particular techniques for rasterizing and updating quantities on the MAC grid. In addition, a heat model may be coupled to the MPM solver, allowing material changes to be driven with temperature and phase changes.

The invention discloses a landslide disaster scene simulation method based on a material point method. The steps are as follows: 1) model and draw the disaster phenomenon of landslide in the field of computer graphics. 2) Based on the traditional MPM method, the yield surface criterion is improved, and the modified Cambridge model is introduced. 3) A two-way coupling model based on MPM for granular material and rigid body interaction is proposed, which makes the soil-rock interaction more realistic during the landslide process and improves the efficiency of large-scale complex disaster scene simulation. The invention solves the problem of lack of landslide disaster scene simulation in computer graphics, and can simulate the movement between soil particles, the collision between rock rigid bodies and the coupling phenomenon between soil particles and rock rigid bodies during the occurrence of landslides .

The invention provides a material point method-based stochastic dynamics analysis method applied to explosion shock engineering. The method comprises the steps of building an engineering physical model; determining stochastic variables and performing discretization; dividing a background grid for a calculation domain; calculating a node load of the background grid, solving a momentum equation, andcalculating first-order and second-order partial derivatives of an accelerated speed of a grid node and an accelerated speed of a material point to basic stochastic variables; updating the position and speed of the material point and first-order and second-order partial derivatives of the position and speed of the material point to the basic stochastic variables; calculating a strain increment and a spin rate increment of the material point; calculating the density of the material point; according to a constitutive model, updating a stress of the material point and first-order and second-order partial derivatives of a stress function to the basic stochastic variables; according to a state equation model, updating a pressure and first-order and second-order partial derivatives of a pressure function to the basic stochastic variables; and calculating a structure stochastic response result. The defects of a conventional numerical calculation method in researching nonlinear problems of explosion, impact and the like are overcome.

The invention provides a CCPDI-IMPM method for large deformation analysis of saturated porous media based on the u-p control equation of generalized Biot theory and convective particle domain interpolation technology. The method includes the analysis of large deformation consolidation process of saturated porous media and saturated Dynamic process analysis of large deformation in porous media. The invention adopts the implicit time integration strategy to overcome the defect of the traditional explicit material point method limited by the critical time step, especially when solving quasi-static problems, it significantly improves the calculation efficiency; The Euler-Lagrangian description advantage of the material point method is more robust than the traditional FEM calculation performance when dealing with large deformation and extreme large deformation. The invention also proposes an extended material point penalty factor method, which is used to deal with the boundary conditions of the fluid-solid coupling system more simply and accurately.

The invention belongs to the technical field of material mechanics, and discloses a method for obtaining material macroscopic three-dimensional equivalent attribute. The method for obtaining material macroscopic three-dimensional equivalent attribute comprises the following steps of (1) establishing a double-scale coordinate system used for describing the material and the microstructure, and constructing a material macroscopic equivalent attribute model based on a progressive extension theory; (2) constructing a periodic boundary model of a three dimensional microstructure; (3) establishing a periodic constraint relation of the three dimensional microstructure through finite element analysis; (4) establishing a linear elasticity equilibrium equation of the three dimensional microstructure based on the periodic constraint relation, and obtaining a displacement field of the microstructure according to the linear elasticity equilibrium equation; and (5) solving unit strain energy based on finite element analysis and the displacement field of the microstructure, and obtaining the material macroscopic three-dimensional equivalent attribute. According to the invention, unit interactive energy is introduced in finite element analysis, a equivalence relation between the total strain energy of the microstructure under the unit test strain and the material attribute is established, and the material attribute is efficiently obtained.

The invention provides a material point method based on an improved contact algorithm, which is applied to double-color coin imprinting forming simulation. The method comprises the following steps of: establishing a dynamic physical model for a double-color coin imprinting forming process; carrying out material point integration on the dynamic model in the imprinting forming process; performing finite element triangle / quadrilateral unit discretization on the forming die; establishing a background grid according to the blank cake data model, performing tetrahedron / hexahedron unit discretization on the bicolor coin blank cake, and establishing a mass point set of a copper and aluminum material area; and calculating strain increment and rotation rate increment of the mass points, solving stress and elastic-plastic related variables of the mass points according to the constitutive model, and updating the density of all the mass points. According to the method, the problem of material self-contact judgment in double-color coin stamping forming finite element simulation is solved through a material point method.