Papers by Keyword: Thermal Stress Field

Abstract: Taking account of the special structure of gradient material and take advantage of good toughness properties of copper,Based on Ansys secondary development technology, using the Gauss moving heat source and the element birth and death technology, a laser direct deposition of graphite copper gradient composite thermal coupling model was developed;On the basis of accurate calculation of the stress field,the generation mechanism of crack in layer by layer and transverse crack and longitudinal crack for the deposition parts was revealed.

Abstract: Compared with conventional ingot, difficulties in melting and casting of large size ZALCu5MnA alloy is due to the increase of ingot size, which lead to a depth increase in smelting bath process, mixing melting liquid is also difficult, and chemical composition of molten pool is not uniform. this paper uses finite element method to analyze the temperature field and thermal stress field of large size ingot of alloy in solidification process, heat transfer model, radiation the boundary condition and latent heat of solidification processing are discussed meanwhile the microstructure of the casting parts surface and center are related researched.

Abstract: The thermal stress field in the polysilicon was simulated and comparatively analyzed at different shapes of crucibes which have different types of a flat, a inverted-conical and concave bottom by COMSOL Multiphysics version 4.3a. The results indicated that: within the flat-bottomed crucible ,the isotherm in the crystal was slightly convex and the area of the maximum thermal stress was distributed in the bottom of the crystal edge and near the top of crystal edge; within the inverted-cone crucible, the isotherm in the crystal was straight and the area of the maximum thermal stress was only distributed in the bottom of the crystal edge; within the bottom of the concave crucible, the isotherm in the crystal was slightly concave and the area of the maximum thermal stress distributed in the bottom of the crystal edge was larger than that of the crystal within the first two kinds of crucibles. To sum up, the inverted-cone crucibe was beneficial to reduce the thermal stress distribution in the polysilicon which could provide theoretical guidance for improving the production process of the polysilicon.

Abstract: In the process of deposition, the moving high energy heat source effect on the metal entity, and form the molten pool and the temperature field of directional conduction. Powder is accumulated in the substrate point by point, molten powder instantly solidify into a solid which is combined with substrate (or sediment) to reach metallurgical combination, from the perspective of the thermodynamic, the temperature field produced by coupling ring of heat source is regarded as a moving load to the base plate and the sedimentary section, and transient thermal stress field is generated, the load and boundary conditions (temperature field) of thermal stress field change over time, at the same time, the solution domain of thermal stress field change over time as a result. Therefore, through the life and death unit technology (ANSYS finite element analysis software of advanced analysis techniques) combined with the circulation order, the simulation of point to add deposition process is realized.

Abstract: Due to the poor conditions of wet brake cooling and the high temperature of the working characteristics, this paper intended to introduce the oil film vadose between the brake linings, considered the variation of volume of grooves on the friction plate, and then proposes the three-dimensional transient dynamic response of fluid-solid coupling mathematical model. By numerical analysis of the disc transient thermal stress field distribution on the friction plate, the friction surface temperature field variation is obtained. Finally, the results shows that the mathematical model is effective and feasible.

Abstract: In order to solve the problem of cracks of the double regenerative burner, six kinds of low stress pass structures were newly developed and corresponding 3D CAE models were set up. With the FEM numerical simulations of thermal stress field of various combinations of different pass structures and the comparative study, the optimized pass structure that the thermal stress is relatively lower and thus can improve the service life of burner was determined.

Abstract: In order to solve the problem of cracks of the double regenerative burner, a kind of new low stress pass structures was developed, and the corresponding 3D CAE model was set up. The results of numerical simulation of thermal stress field of the new pass structure showed that the thermal stress and stress amplitude of the new pass structure is relatively lower and thus can improve the service life of burner.

Abstract: In this paper, the thermal stress characteristics of polystyrene plate - thin plaster wall are present. A three-dimensional element is selected to mesh the wall model, which can simulate the coupling effects of thermal stress and structural stress field. Thermal stress and deformation distribution are proposed after comparing and analyzing the two simulation results. Numerical simulation results indicate that: (1) Polystyrene plates thin plaster wall insulation system has very good thermal insulation properties；(2) Different stress fields concentrate significantly around windows and in the middle of wall especially around the windows. (3) The deformation of the polystyrene plate - thin plaster wall insulation system reach the maximum at the edge of the wall while the minimum in central.

Abstract: The process of injection molding, packing and cooling for injection mold PET (Polyethylene terephthalate) cavity was analyzed and the cause of fatigue stress cracking was investigated. An analysis method of injection mold cavity fatigue based on Ansys Workbench(AWB)was put forward. A simulation of temperature field, displacement, thermal stress field and fatigue life for the cavity of a work cycle based on heat transfer theory was completed. Provide effective measures to avoid fatigue stress cracking and optimization design of the injection mold.

Abstract: In this paper, the finite element simulation of laser drilling process has been carried out for the nickel alloy DD6. Both the transient temperature field and thermal stress field were computed via the commercial software package ANSYS. Based on the method of dimensional analysis, the dependence of various non-dimensional parameters on both fields was specified and demonstrated in graphical forms.