Abstract: Compared with common permanent magnet (PM) machine, the high speed PM machine has smaller size and larger power density. However, owing to high-speed high frequency and small volume, the PM rotor is more easily to become overheated so that irreversible demagnetization of the PM is induced. Traditional cooling methods of machine directly cool the machine stator, the temperature rise of rotor is reduced through heat exchange among stator, air gap and rotor. Owing to rapid temperature rise of high speed PM machine rotor, the method of indirect cooling rotor does not effectively protect PM rotor from overheating. To directly reduce the temperature rise of PM rotor and the volume of machine, design method of fan-cooling for high speed PM machine rotor is proposed in this paper, that is, high speed axial fan rotating synchronously with the high speed PM machine rotor is designed. Finally, the temperature rise of high speed PM machine rotor with the structure of high speed axial fan is analyzed based on the coupling method of fluid-solid, the validity is verified.
Abstract: This paper aims to highlight the utility of implementing the Reverse Engineering Technique in designing assembly parts in the field of industry. Starting from the iconic part models the project begins with the specific stages for Reverse Engineering technique, the part digitization by means of a 3D scanning system, followed by the reconstruction of the solid type parts, and ending with their parameterization. Parameterization is of great importance especially in what concerns the automated obtaining of the part models, since this allows updating the solids along with the change of parameters. In this paper it will be also presented a case study - done by means of the CATIA software package – which demonstrates the creation of parametric solids starting from physical parts for which no technical documentation is available.
Abstract: As is known to all, new mechanical product design is always on the basis of the original product, so to better use the exiting design resource, a mechanical product variant design method is presented. The new method is based on SML and parameter CAD. According to different geological conditions of coal mine, different types of hydraulic support are needed to design. So as a typical kind of mechanical product, hydraulic support is given as an example to demonstrate the new variant design method. Finally with SOLIDWORKS as a specific application object, integrated with SQLServer2000 database, a hydraulic support variant design system is realized by Visual Basic program, which shortens the cycle of mechanical product development and reduces duplication mechanical design greatly.
Abstract: Aiming at the seriously nonlinear problems of the single nozzle thrust vector control servo system, this paper detailedly deduced the functional relations between the layout of actuators and system dynamic parameters, on the basis of which, a multi-objective optimization model was established with coupling degree, angular asymmetry, as well as length and variation degree of initial swinging arm taken into consideration. Linear weighting method was adopted to convert the multi-objective function into a uni-objective one and an improved genetic algorithm with good robustness was utilized to solve the optimization problem. Calculation results demonstrated that, with this optimization algorithm, sub-objective functions all reach the ideal effects when uni-objective function achieves optimum. The optimization method guarantees that coupling degree, angular asymmetry and swinging arm variation achieve minimum when the initial swinging arm length is at its maximum, which provides theoretical basis for the actuator layout of thrust vector control.
Abstract: A locomotive-type turbocharger compressor with 24 blades under combined centrifugal and interference-fit loading was considered in the numerical analysis. The solution of elastoplastic frictional contact problems belongs to the unspecified boundary problems where the interaction between two kinds of nonlinearities should occur. To save the time cost in the numerical computation, multi-substructure technique was adopted in the structural modeling. The effect of fit tolerance, wall thickness of shaft sleeve and rotational speed on the contact stress was discussed in detail in the numerical computation. To decrease the difficulty of the assembling process and make sure the safety of the working state, the amount of interference between the shaft sleeve and shaft by press-fitting should be controlled strictly to avoid the rapid increase of the contact stress. The numerical results show the high accuracy and good convergence of the algorithm presented here. The study play a referenced role in deciding the proper fit tolerance and improving design and manufacturing technology of compressor impellers.
Abstract: Selecting the favorable conceptual design scheme is the first step to make a new product development (NPD) successfully. To guarantee reliability and rationality of decision-making about multiple design schemes in conceptual design stage under the impact of uncertainties and qualitative information, we have employed KJ method to cluster the evaluation factors into 5 clusters such as emotion, ergonomics, aesthetics, core technology, and impact; and fuzzy mathematics method to deal with uncertainties and qualitative information effectively. The weights of evaluation factors were calculated by analytical hierarchy process (AHP). Fuzzy mathematics method is the comprehensive evaluation method and quantitative analysis which based on the “maximum membership degree evaluation”. All design schemes are ranked and selected according to the multiple evaluation score of parts with their weights. Finally, a case study for decision-making is presented to demonstrate the application of the evaluation method.
Abstract: The revolving jet is a technique method of using the water to eliminate shallow submersion land mine surface, it can be also used in the clearance of mine, the unique characteristic is the main use of shear broken, erosion crushing, stretch broken cyclone grinding effect on the topsoil which is on shallow mines. this technology research and the application. Based on the revolving water jet flow theory and soil mechanics theory, by means of the action of the jet flow to the soil body surface and the mechanism of the revolving jet flow breaking ground analysis, and the thoughts of which the action pressure of jetting is basic external factor of the soil body destruction, but the soil body critical destructive power to soil body is determined by its internal factors that physical and mechanical properties of the soil, only then, when the jet flow action is greater than the soil body the critical destructive power, the soil body only then possibly has the destruction. This technology research and the application not only raise efficiency of the mine clearance, but also further expand application scope of the water Jet. Based on water jet test platform of the laboratory, in order to make the revolving jet produce the greatest ground-breaking efficiency. the swirling jet nozzle and rotating components are optimized for it.
Abstract: Pine furniture is becoming increasingly popular among customers. With the aim of improving pine furniture design and manufacturing, this paper analyzes the basic material properties of pine, such as the color, the texture, the shape and the structure of its parts. The technical design methods for the framework, panel, and shelf structures are also discussed. The fundamental principle on the style and design method of pine furniture is summarized. The results show that the influence of the knots and flaws, the turpentine and moisture content, the paint decoration and colors, the textures and veins, the shape characteristics of furniture parts, the basic structure forms of furniture units, and the connection methods significantly great affects pine furniture design. According to the basic design principles and methods, designers can obtain fine pine furniture.
Abstract: Nowadays, with the increasing prominent contradiction between waste of product packaging and environment, people gradually realize the importance of green packaging. Through accessing to bamboo packaging related to the analyzing summarizing and studying, the paper deduces the characteristics of green packaging which are green packaging material, reasonable packaging structure, combined with local and traditional culture. Based on studying on packaging of Shanxi Liangpi, the paper aims to find out ways and reasons about the feasibility of green packaging.