Advanced Materials Research Vols. 189-193

Abstract: With the more profound requirements for knowledge resource application in the complex production collaborative design, a complex production design method based on knowledge model driven was put forward with the development trend of intelligent design theory. The knowledge mining oriented the key phases of complex production design process, knowledge modeling with its reuse are the core of the method. The system framework of the design method was structured. This method supports the whole process of product design, it truly realized sharing, reuse and seamless integration among product model, task model and process model through the ontology model as a knowledge carrier. Finally, the thrust bearing-a key component of hydropower generating units, for example verify the correctness of the design methodology and feasibility.

Abstract: Considering gyroscopic effect and flexibility of the shaft, the eight freedoms dynamic model is established. The dynamic characteristic and control quantity in different bearing rigidity and rotation axis are studied and discussed by optimal control theory. Furthermore, the controlling and the responding are discussed. The simulation results show that the bearing rigidity has great effect on the control quantity so that the elasticity of bearing must be considered. The asymmetry rigidity of rotational axis has little influence on stability. The conclusion may bring up theoretical references for precision control for rotor magnetic bearing system.

Abstract: The virtual design platform for large mine elevators was established by using the informationization unit technology of manufacturing industry in this paper. On the basis of the virtual design and manufacture platform, 3D digital design, computer-aided analysis and computer-aided process planning under the support of network system were carried out. The informationization standard system for the design and manufacturing of the mine elevator equipments was established. The information classification code of the whole procedure of product design and manufacturing was normalized and unified. A type of multirope friction mine elevator, numbered as JKM-4.5×6, has been developed and put into practice. By means of the virtual design and manufacturing technology, the product design quality could be enhanced. Meanwhile, the manufacturing procedures of prototypes were simplified and cancelled, so that reducing the cycle and cost of the product development. This study results may be helpful for the development of large-sized equipments.

Abstract: There are two protection structures for duralumin sheet, including surface anodizing and spraying ZrO₂ coating, designed for preventing damage induced by laser. In this paper, for anodized aluminum sheet and ZrO₂ coated sheet, the ability for laser protection has been simulated and analyzed. The thermal model of sandwich material is established and a finite element method (FEM) code is developed. The rule of the thermal effects in two structures induced by laser irradiation have been discussed, under chosen requirements of laser protection, including that laser power density is 500W/cm²; irradiation time is 3s; the aluminum sheets cannot be much thicker than 3mm; reflectivity cannot be much than 0.6. And the calculation results are verified experimentally and can give a guide to design for laser protection.

Abstract: Electronic package development is driven by the continuous increase in demands for miniaturization of products with enhanced performances. Three Dimensional System in Package (3D SiP) has become a key technology to satisfy the request. The 3D SiP with Through Silicon Via (TSV) technology is developed for chip to chip stacking in a package with superior electrical performance than conventional structures. In this study, we evaluate the thermal performance of 3D SiP with TSV technology using Finite Element Method (FEM). The evaluation topics covered impacts of various materials of mold, 3D SiP models with and without TSV, and various convention conditions. The results indicated that the role of TSVs in heat dissipation is not obvious in this study, and the maximum temperature merged in the center of the chip1 under different conditions which are considered.

Abstract: The realization of a fusion reactor is critically dependent on the successful development of high performance materials. Especially, the plasma facing components (PFCs) which basically consist of a direct plasma facing armor material and a heat sinking material. Tungsten (W) and Copper-alloy (CuCrZr) have been considered as the potential candidates for armor materials and heat sinking materials, respectively, due to their attractive nuclear and physical properties. However, due to the incompatibility of the coefficient of thermal expansion and the elastic properties between the W and the Cu-alloy as well as the non-homogeneous temperature distribution in PFCs, one of the crucial issues is the generation of thermally-induced residual stresses in W/CuCrZr PFC on cooling either during fabrication or during operation of fusion reactor. Therefore, the thermo-mechanical response of PFCs under high heat flux from the fusion reactor is a critical issue for the development of fusion technology. In the present work, in order to optimize the thermal and mechanical integrity of PFCs, thermally-induced residual stresses in W/CuCrZr PFCs with a compliant interlayer (OFHC-Cu: Oxygen Free High Conductivity Copper) are analyzed numerically by means of finite element method. Result indicated that the use of interlayer in PFCs could significantly reduce the magnitude and the concentration of thermally-induced stresses in comparison to the PFCs without interlayer. And also the optimum thickness for interlayer was suggested based on the current analysis conditions.

Abstract: The influences of longitudinal gradient on the large longitudinal slope rigid base composite road of cross river(sea) tunnel are concerned recently. Then the relationships between sheering stresses versus slope angle, load, pavement depth, interlayer touch condition and modulus are discussed separately by a three dimensional FEM model. Calculation and analysis showed: gradient had great influence on the surface tangent load and little influence on design deflection, the base and surface.The maximum tension and sheer on surface were increased with the gradient. On general, the gradient and surface tangent load should be considered in structure analysis for the large longitudinal slope road.

Abstract: In order to effectively represent assembly process information based on three dimensional (3D) models and rapidly extract the necessary information for assembly process planning, analysis and simulation, this paper aims to research the multiple view representation of assembly process information based on 3D models. Assembly process information based on 3D models is summarized and considered as the single source of the multiple view representation. The definition and organization of assembly process view is defined to implement assembly process representation based on view. Assembly process views based on assembly process planning work flow are established. View mapping approach is investigated to rapidly extract the necessary information for assembly process planning, analysis and simulation. The use of the multiple view assembly process representation is illustrated by building detailed assembly process view and assembly process simulation view and by extracting relevant information for the assembly process simulation view from detailed assembly process view.

Abstract: In order to correctly analyze the effect of water vapor cooling in metal cutting process, the turning process of AISI 1045 in the water vapor cooling condition is simulated using a commercial finite element software Deform-2D, including geometric modeling, meshing, boundary condition setting and material modeling, etc. The cutting temperature in different cooling conditions are then analyzed and discussed. The experimental validation showed a good agreement with simulation results. Thus, FEM simulation of cutting process can be considered as a promising and reliable tool for machining development within the near future.

Abstract: This paper presents a method of piston stroke design optimization for linear compressor to get high efficiency.Two linear compressor prototypes were designed and developed with the same discharge volumes and different piston strokes to compare the performance. The prototypes were operated without air load to measure the friction damping coefficient firstly. Then the prototypes were operated with air load of 0.7MPa discharge pressure. The experimental result shows that the input power of the prototype with longer stroke is lower than that of the prototype with shorter stroke although the discharge volume, the friction damping coefficient and the frequency ratio of these two prototyps are almost the same. The iron and coil loss of the prototype with longer stroke is lower than that with shorter stroke, while the mechanical loss of the prototype with longer stroke is larger than that with shorter stroke. According to the results of the performance analysis, a design optimization model for piston stroke is developed to make the energy loss be the least. Through this design optimization model, acquire the optimal piston stoke of the linear compressor on the same conditions with the experiment. The optimization results agree well with the experimental results.