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The paper presents a practical implementation of hybrid simulation using Real Time Finite Element Method (RTFEM). Hybrid simulation is a technique for investigating dynamic material and structural properties of mechanical systems by performing numerical analysis and experiment at the same time. It applies to mechanical systems with elements too difficult or impossible to model numerically. These elements are tested experimentally, while the rest of the system is simulated numerically. Data between the experiment and numerical simulation are exchanged in real time. Authors use Finite Element Method to perform the numerical simulation. The following paper presents the general algorithm for hybrid simulation using RTFEM and possible improvements of the algorithm for computation time reduction developed by the authors. The paper focuses on practical implementation of presented methods, which involves testing of a mountain bicycle frame, where the shock absorber is tested experimentally while the rest of the frame is simulated numerically. [ABSTRACT FROM AUTHOR]

Material which has character exists on thermoplastic, battery, coating material, and etc. The existing event is in transient’s condition. Transient situation on geometrical shape and complex boundary condition is difficult to solve by analytical method. The solving transient’s situations will be done using finite element method (FEM) that is solved by computer. Bar metal that is got thermal loads in the period of long time then it will be soaked into liquid to change metal bar physical property it. For this need careful analysis that is safety on metal bar utilized on structured component and also constant nuclear component guarded. It should be done using modeling and computer simulation. This paper, describes about transient temperature distribution analysis that is observed from center, corner edge, and center external surface on cross section got from a rectangle shape which is suddenly quenched up to 3 seconds into liquid with temperature t£, convective surface coefficient h and initial temperature t0. The Characteristic is an orthotropic having X-axis conductivity value different from X-axis conductivity value. The solution of problem mentioned above is done by software application based on finite element method. [ABSTRACT FROM AUTHOR]

A finite element model of three-dimensional high speed machining is developed. In order to catch Adiabatic Shear Band (ASB), which is about few microns wide, the simulation uses mesh adaptation triggered by an isotropic error estimator. An enhanced version of the Zienkiewicz and Booromand REP in Patches technique is used. As ASB is a much localized phenomenon, the adaptive procedure provides highly refined meshes with strong gradients of the element size, which makes it quite difficult to produce satisfactory 3D meshes. Furthermore, high speed machining leads to very important values of strain rate, deformation and possibly to extreme mesh distortion. So, an Arbitrary Lagrangian Eulerian (ALE) method is employed. With the utilized splitting method and linear finite element interpolation, the transport of nodal variables is based on the gradient calculated in the upwind element. For variables stored at the integration points, a remapping procedure using patch recovery techniques is preferred. Finally, because of the very strong thermo-mechanical coupling taking place in ASB, several thermo-mechanical coupling schemes are studied. Explicit and fully implicit schemes are compared, showing that the second one offers a stabilizing effect and a better accuracy. All of these ingredients provide a fully automatic and process independent procedure which allows detecting and following the formation of Adiabatic Shear Band in High Speed Machining. The creation of 3D segmented chip is observed and compared to 2D reference results obtained by Baker in [1]. The influence of numerical coefficients like the mesh size is investigated. Other application to actual 3D high speed machining such as blanking is also presented. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]