30 results about "Continuum mechanics" patented technology

The invention discloses a method for solving a nonlinear mechanics problem of a continuous medium member by applying a three-dimensional discrete entity. For the limitation of a conventional discrete unit method for calculating a continuous medium problem, discrete element models of two three-dimensional discrete entities are built by taking energy equivalence as a principle based on a mechanics theory of a continuous medium; by adding a contact spring between particle units, the Poisson ratio effect of a material is reflected; and an analytic relationship between a mesoscopic model parameter (spring stiffness) and macroscopic elastic constants (an elastic modulus and a Poisson ratio) is derived, so that a great breakthrough is achieved in simulation of the continuous medium with a large Poisson ratio in PFC software. In addition, a plastic part is added in a contact constitutive equation between the particle units. According to the method, the elastic-plastic problem of the continuous medium can be effectively subjected to simulative calculation analysis by adopting a discrete entity unit method; and the method is suitable for nonlinear mechanics problems of large deformation, damage fracture, collapse destruction and the like of a structure or the member.

The invention discloses a finite-element analysis, monitoring and support method of soft-rock slope stability. The method includes the following steps: step one, obtaining rock slope failure types, slope stability influence factors and slope reinforcement support measures by induction, establishing a mechanical model of engineering geology simulation analysis under the action of the different influence factors, and analyzing a dominant factor controlling the soft-rock slope stability and a potential mode thereof; and step two, using an approximate equivalent physical model, which is formed bya plurality of mutually associated unit bodies, by a finite-element analysis method of the slope stability to replace actual structures or continua, and establishing equations, which characterize force and displacement relationships, through basic principles of structure and continuum mechanics and physical characteristics of units. The finite-element analysis, monitoring and support method of thesoft-rock slope stability uses the finite-element method to analyze the stability thereof, carries out support and treatment on places where danger may further occur, and has certain guiding significance for solving slope stability problems.

The invention provides a method for computational fluid dynamics and apparatuses making enable an efficient implementation and use of an enhanced jet-effect, either the Coanda-jet-effect, the hydrophobic jet-effect, or the waving-jet-effect, triggered by specifically shaped corpuses and tunnels. The method is based on the approaches of the kinetic theory of matter, thermodynamics, and continuum mechanics, providing generalized equations of fluid motion. The method is applicable for slow-flowing as well as fast-flowing real compressible-extendable fluids and enables optimal design of convergent-divergent nozzles, providing for the most efficient jet-thrust. The method can be applied to airfoil shape optimization for bodies flying separately and in a multi-stage cascaded sequence. The method enables apparatuses for electricity harvesting from the fluid heat-energy, providing a positive net-efficiency. The method enables efficient water-harvesting from air. The method enables generators for practical-expedient power harvesting using constructive interference of waves due to the waving jet-effect.

The invention provides a modularized cord-driven continuum mechanical arm. The modularized cord-driven continuum mechanical arm comprises a plurality of modularized single bodies, a first hinge joint part and a second hinge joint part are arranged on the opposite surfaces of every two adjacent modularized single bodies respectively, the first hinge joint part of one modularized single body and the second hinge joint part of the other corresponding modularized single body form a hinge joint structure, the modularized single bodies are sequentially in hinge joint through the hinge joint structures to form mechanical arm joints, and the modularized single bodies are provided with function holes and cord passing holes arranged circumferentially sequentially. The modularized cord-driven continuum mechanical arm has the advantage that through different connecting and locking modes adopted between every two adjacent modularized single bodies, different continuum mechanical arms different in flexibility and load capacity can be obtained.

The invention relates to a dynamic response analysis method for a saturated soil-group pile-upper structure system, and belongs to the technical field of pile foundation mechanical analysis. Accordingto a porous media theory established by de Boer based on a continuum mixture axiom and a volume fraction concept, by utilizing the volume fraction concept, a plurality of microscopic properties can be described directly through macroscopic properties, and complex formulae in a hybrid mixture theory are avoided. The porous media theory established by the de Boer not only conforms to continuum mechanics and thermodynamics principles, but also has numerous advantages which a Biot theory does not have. In addition, for the situation that the research of pile-soil-upper structure dynamic interaction is limited to single-phase soil, little saturated soil is involved. Due to the existence of a liquid phase, the propagation and dissipation of energy and waves in the saturated soil and the single-phase soil are different; the influences of the filtering and amplifying effects of a soil layer on seismic waves under the action of seismic loads on structure seismic response characteristics are different; and the method is of great practical significance.

A system and method that relies on the principles of material science, deformable body mechanics, continuum mechanics and additive manufacturing to reduce the costs associated with additive manufacturing. Physical properties are used by numerical solution methods, such as the Finite Element Method (FEM) or Smooth Particle Hydrodynamics (SPH), to deform an original model of an object to be manufactured into a viable configuration that reduces fabrication material, time, and cost when manufacturing an object through additive manufacturing.

The invention discloses a method for determining the safe drilling fluid density of a coal bed based on a structural element analysis model. The method has the advantages of coal bed cleat and fracture development, big rock brittleness, low strength and obvious anisotropy and discontinuity. The borehole wall instability characteristics of the method are different from those of the common sandstone stratum. The phenomenon that the traditional borehole wall stability model based on the mechanics of continuous media is difficult to be successful for solving coal bed instability problems can be eliminated. In the method, the coal bed is composed of discrete blocks. A coal briquette which has the biggest possibility of generating spallation between surface cleats is analyzed to carry out force analysis. A structural element model of collapse pressure is built by the stressed balance condition among pressure stress, shearing strength and shaft pressure. A coefficient c is introduced to judge the stable relationship of borehole pressure and borehole wall so as to judge the range of the safe drilling fluid density.

The invention discloses a blood coagulation simulation method based on MPM, including: initializing a general data, 2, discretizing the blood into particles and grid; S3, simulating blood coagulationaccording to substance point method. The invention also discloses a blood coagulation simulation method system based on MPM. The present invention can be based on MPM frame, combined with continuum mechanics and fluid mechanics N-S equation and Lame coefficient function is designed according to the blood coagulation rate to accurately simulate the blood coagulation process.

The invention provides a fluid-solid coupling high-precision numerical simulation method based on continuous medium mechanics, and belongs to the technical field of fluid-solid coupling numerical simulation. The implementation method is as follows: based on an intrinsic non-oscillation (WENO) finite difference method, a joint algorithm coupled with a Level-Set method and a real virtual fluid method (RGFM), high-precision numerical simulation of fluid-solid coupling of continuous medium mechanics is realized. The WENO finite difference format can realize high-precision spatial discretization byselecting spatial template lattice points, so that the calculation precision is ensured, and the dissipation of shock waves is remarkably reduced; the Level-Set method can be used for effectively processing the complex topological structure change of the multi-substance interface; The RGFM method can effectively restrain the problem of non-physical oscillation generated by the interaction of shock waves and a material interface. The method can improve the prediction accuracy of the fluid-solid coupling process, and further solves the related engineering technical problems in the fluid-solid coupling field. The fluid-solid coupling field comprises the fields of high-speed penetration weapons, protection equipment, aerospace and mechanical engineering.

The invention discloses a sidewall stability research method suitable for a pressure-depleted formation. In the method, knowledge points of multiple disciplines, such as the underground rock mechanics, the borehole geophysics, the continuum mechanics, the elastic mechanics and the mathematical statistics, are integrated, the method starts with microscopic deformation conditions of rock skeleton particles obtained after the formation pressure is depleted till to the macroscopic acoustic response performance, characteristic parameter variation and the like of rocks, makes full use of partial data, such as rock skeleton density logging, shale content logging, actual measurement points of the formation pressure and collapse and fracture pressure and the formation core, obtained when the oilfield formation pressure is not depleted, and finally the collapse and fracture pressure of the pressure-depleted formation is determined, so that guidance and reference are provided for selection of the density of a drilling fluid for pressure-depleted formation drilling. The computing method is high in precision, and just a few of errors exist in fracture pressure prediction.

The invention discloses a Taylor-Courte experimental device for solid media, which relates to the field of continuum mechanics. The device comprises a cylindrical sample chamber composed of inner and outer cylindrical walls and two annular end faces; and a driving sample The drive mechanism for the relative rotation of the inner and outer cylindrical walls; the torque sensor recording system for recording the relative rotational torque of the inner and outer cylindrical walls of the sample chamber; it also includes a pressurization mechanism that provides axial pressure to the end of the sample in the cylindrical sample chamber; records the sample The pressure sensing recording system for the axial pressure on the end; the information acquisition system for recording the rheological conditions of the solid medium of the sample. The device has a simple structure and is easy to implement, and can extend the research of the rheological behavior of the liquid medium to the rheological research of the solid medium from the classical Taylor-Couette device.

The invention discloses a method for solving a nonlinear mechanics problem of a continuous medium member by applying a three-dimensional discrete entity. For the limitation of a conventional discrete unit method for calculating a continuous medium problem, discrete element models of two three-dimensional discrete entities are built by taking energy equivalence as a principle based on a mechanics theory of a continuous medium; by adding a contact spring between particle units, the Poisson ratio effect of a material is reflected; and an analytic relationship between a mesoscopic model parameter (spring stiffness) and macroscopic elastic constants (an elastic modulus and a Poisson ratio) is derived, so that a great breakthrough is achieved in simulation of the continuous medium with a large Poisson ratio in PFC software. In addition, a plastic part is added in a contact constitutive equation between the particle units. According to the method, the elastic-plastic problem of the continuous medium can be effectively subjected to simulative calculation analysis by adopting a discrete entity unit method; and the method is suitable for nonlinear mechanics problems of large deformation, damage fracture, collapse destruction and the like of a structure or the member.

The invention discloses a large-scale particle material internal stress and crushing simulation analysis method and device, which belong to the technical field of particle crushing. Based on the basic idea of ​​continuous discrete coupling, the invention combines the boundary element method and discrete element method to carry out large-scale particle crushing research , can use the boundary element method to calculate and analyze the internal stress of the particles, and combine the fracture theory of continuum mechanics, and the Hawke-Brown criterion to judge whether the particles are broken. In addition, when using boundary elements for internal stress simulation, for particle aggregates with similar shapes, such as round particles, the present invention only needs to calculate the coefficient matrix of one particle, and other similar particles obtain the coefficient matrix through coordinate conversion and coefficient scaling. The calculation efficiency is greatly improved. The invention also simulates the internal stress of the circular rockfill material and proves its effectiveness.