Method and apparatus for simulating a mechanical operation

• US 5,402,366 A
• Filed: 11/13/1992
• Issued: 03/28/1995
• Est. Priority Date: 11/14/1991
• Status: Expired due to Fees

• Current Assignee: Sumitomo Heavy Industries Limited
• Original Assignee: Sumitomo Heavy Industries Limited
• Inventors: Yoshii, Akihiko, Kihara, Shigefumi
• Primary Examiner(s): Voeltz, Emanuel T.
• Assistant Examiner(s): Tran, Alan
• Application Number:
  US07/976,505
• Time in Patent Office: 865 Days
• Field of Search: 364/578, 364/476, 364/149, 364/505, 364/508, 228/121, 228/122, 228/120, 73/826, 73/799, 73/147, 73/823, 73/804, 73/783
• US Class Current: 703/9
• CPC Class Codes: G01N 11/00 Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties
• CPC Class Codes: G01N 2203/0216 Finite elements
• CPC Class Codes: G06F 2113/22 Moulding
• CPC Class Codes: G06F 30/23 using finite element methods [FEM] or finite difference methods [FDM]

Abstract

A method and apparatus for simulating a mechanical operation is based on the finite element method and uses a particle flow model. Evaluation of contact boundary between a die and a material and remeshing operation are unnecessary. Particles (6) are moved on fixed elements to change material properties therein. The elements per se are not deformed.

Claims

1. A method for simulating a mechanical operation by monitoring a flow of a deformable material, said method comprising the steps of:

initially defining an analysis space which includes a first analysis region filled with said material and a second analysis region free from said material;

dividing said analysis space into a plurality of divided elements over said first and said second analysis regions;

distributing particles in said divided elements which are located in said first analysis region; and

monitoring movement of said particles in said analysis space with reference to at least one predetermined material property of said material, said analysis space being kept unchanged while said first and said second analysis regions are changed with time.

2. A method for simulating a mechanical operation as claimed in claim 1, wherein the simulation is carried out by the use of a finite element method with reference to change of physical values of said divided elements, said change being caused by displacement of said particles moved on said divided elements.

3. An apparatus for simulating a mechanical operation by a die and numerically simulating a flow and deformation process of a deformable material molded by movement of said die using the finite element method, comprising:

an arithmetic model generator for defining an analysis space which includes a first analysis region occupied by said material and a second analysis region where said material is not present, modelling said first and said second analysis regions into finite element models, and distributing particles in said first analysis region to represent a shape of said material;

a velocity field calculator for calculating a velocity field in said analysis space in accordance with said die and said material so that energy dissipation in said analysis space has a minimum value under a predetermined boundary condition, said velocity field being given by a first nodal velocity of said divided elements in said first analysis region where said particles are present and a second nodal velocity of said divided elements in said second analysis region where said particles are not present;

a velocity calculator for calculating a moving velocity of said particles from said velocity field;

a position calculator responsive to said moving velocity calculated by said velocity calculator for calculating position information of said particles after being moved; and

a physical value calculator responsive to said velocity field for calculating physical values of said divided elements.

4. An apparatus for simulating a mechanical operation by monitoring a flow of a deformable material within a defined analysis space, said material having a predetermined material property, said apparatus comprising:

dividing means for dividing said analysis space into a first analysis region filled with said material and a second analysis region free from said material;

dividing means for dividing said analysis space into a plurality of elements over said first and said second analysis regions;

distributing means for distributing particles in the divided elements which are located in said first analysis region; and

monitoring means for monitoring movement of said particles in said analysis space with reference to said predetermined property of said material.