Papers by Author: Wan Shan Wang

Abstract: For ultra-high-speed grinding, the deformation of grinding wheel has a greater impact on the machining accuracy. Finite element method was used to study the radial deformation of the CBN grinding wheel considering centrifugal force and grinding heat. The study shows that the effects of centrifugal force and grinding heat are same magnitude, and the proportion changes with the change of grinding speed and grinding force. By finite element analysis, it is possible to solve the grinding wheel the radial deformation and grinding temperature under different grinding speed and grinding force, and it also provides theoretical support for predicting the machining accuracy, compensating precision and avoiding grinding burn.

Abstract: The deformation of the spindle system is the main factor affecting the accuracy of ultra-high speed grinding. To calculate the deformation of ultra-high-speed grinding spindle system is required to consider not only the formation of structural deformation, but also the thermal deformation. Using the simulation method, oil temperature and grinding force are calculated in this paper. Based on these two factors, the thermal-mechanical deformation of the hybrid spindle system is analyzed and calculated with the method of FEM. the This article uses simulation methods, analysis and calculation of the oil film temperature rise and the grinding force caused by deformation of the liquid and hydrostatic spindle system factors. The methods presented in this paper can be used in digital design of various kinds of spindle systems, in order to improve the accuracy of the spindle system design.

Abstract: Based on three dimensional modeling software Solidworks, the physical model of 2MW wind turbine’s gear box is constructed and transferred into ADAMS, and then the virtual prototype model of the gearbox is established by adding constraint and load. According to the working state of the gearbox in different wind, the dynamic simulation is carried out, obtaining the revolution of the output shaft and mesh force of all gears. The simulation results compared with the theoretical values to verify the accuracy of the simulation.

Abstract: In the article, blade element momentum theory is used for calculated aerodynamic load of blade under the different wind velocities. 3D model of key functional components such as blade, tower, hub and nacelle are modeled in Solidworks, the MNF files of blade and tower are gained in finite element analysis software after flexible processed, and the rigid-flexible multi-body dynamic model of the wind turbine’s key components is created in ADAMS. Through simulation of the model under constant rotate speed, kinematics and dynamics curves are got while the wind speed rise from 5m/s to 25m/s. This simulation can imitate vibration performance ideally. A feasible method is provided for the virtual prototype simulation of wind turbines.

Abstract: Dynamic characteristics is the foundation of the dynamic design of the machine tool, while the key factor of establishing the accurate dynamic model of the machine tool is the treatment of the joint surface. In this paper, the whole machine tool model is built with the software PRO/ E, and the software MSC. Patran is used to mesh the finite element of super-high-speed grinder and set up the boundary conditions. Then Yoshimura method is used to determine the junction parameters and establish the dynamic model of the junction. The software MSC. Nastran is used to analyze the modal of the whole machine. At last, on basis of identifying the weaknesses of the structure of the machine tool, the paper provides a theoretical basis for the improvement of the machine tool design.

Abstract: Grinding is an important method for precision machining and ultra-precision grinding. It is used to generate parts with high surface finish, high form accuracy and surface integrity. In recent years, grinding technology in precision machining and ultra-precision machining of ceramics, glass and high-strength alloys and other hard materials has been applied widely. Grinding process is complex, once known as "black processing technology." Computer simulation is an important method to research the grinding mechanism and optimize the grinding process parameters. Especially in recent years as the development of computer calculation speed, the improvement of computer graphics theory and the gradual maturity of artificial intelligence technology, experts and scholars whose research subject related grinding had done a lot of work on grinding simulation. This paper gives an overview of the current state of the art in simulation of grinding processes: Physical simulation (material removal mechanism, grinding force, grinding temperature, etc.) and geometrical simulation (surface topography and surface integrity) are taken into account, and outlined with respect to their achievements in this paper. Furthermore, the capabilities and the limitations of the presented simulation approaches will be exemplified.

Abstract: Compared with other metal edged cutting, grinding research is immature on aspect of grinding mechanism and experimental research. With the development of computer technology, FEM is widely used in research of metal cutting process. In this paper, macro simulation of surface grinding is researched with the software MSC.Dytran, and the corresponding experimental study is carried out. On the basis of discussing the simulation cases, the simulation result, especially, grinding force, are analyzed. The simulation and experimental result are basically consistent with the theoretical result.

Abstract: Due to having the features of high accuracy, high stiffness, high load capacity and longer service life, the hybrid bearing spindle system is widely used in grinding. This paper presents an analysis method of hybrid bearing spindle dynamic characteristics. The method uses CFD method to solve the oil film pressure field, instead of Reynolds equation, in order to obtain the oil film stiffness and damping. With the obtained oil film stiffness and damping to build the appropriate constraints, 3D finite element model of the hybrid bearing spindle system is established, and the modal analysis of the spindle system is carried out. Compared the analysis results with the theoretical calculation results, the feasibility and correction of the method are proved.

Abstract: The paper presents a Web-based virtual machine tool system construction method. The key technologies required to build the system were analyzed. A simulation platform is built with ASP technology, and the geometric simulation is researched by using VRML, JavaScript, and JavaApplet. The physical simulation is researched by using Matlab Web Server, The object of the virtual machine tool simulation system is ultra-high speed grinding test bench. The developed system can realize virtual assembly, CNC code identification, material removal simulation, grinding force calculation and optimization.

Abstract: It is different from the traditional integrated super high-speed grinding wheel, the centrifugal force has greater impact on segmented grinding wheel in super high-speed rotation. In this paper, in order to ensure the safety of super high-speed grinding wheel, models for the connection between inner micro-unit’s displacement and stress of wheel matrix were established to optimize high-speed grinding wheel section form, reduce the centrifugal stress and control the radial displacement of grinding wheel. Consider the structural and mechanical characteristics of wheel matrix, strength check of the theoretical formula were also established. Taking into account the factors of aerodynamic and wheel connector effects, at last the design of segmented super high-speed grinding matrix was optimized with finite element method.