Abstract: In this paper, an integrated methodology of geometric modeling, finite element method (FEM) and artificial neural network (ANN) is proposed for design optimization of cold forging process. Forging processes with some key design variables are firstly simulated using rigid-plastic FEM so as to create training data for the ANN model. Then neural network model is used to predict for unseen data after being properly trained. Finally, some forging experiments are carried out to confirm the ANN prediction results, a good agreement is found between the predicted data and the measured results.
Abstract: By systematical research on the analytic procedure of excitation loads inside the internal combustion engine, the computational method of dynamic characteristics and dynamic response, and the prediction technique of structural acoustic radiation, an approach for structural acoustic radiation prediction of I.C.E based on BEM theory, ATV technique and coupled BEM-FEM method is proposed. It is a new and efficient way to solve the problem of engine’s structural acoustic radiation under multi-operating conditions. The numerical simulation results and measured values through experiments indicate that this approach is scientific, correct and feasible.
Abstract: The deformation of an injection-molded part of a motorcycle seat support during the free-cooling stage after ejection was studied by an experimental and numerical method. Numerical analysis of heat transfer based on the uneven temperature distribution measured in the seat support was employed to re-construct the initial temperature field of the part. The temperature field was then introduced into the FEM codes to calculate the deformation of the ejected part due to thermal-stress during the free-cooling stage. It was found that the high and uneven temperature distribution of the part leads to an uneven shrinkage during cooling after ejection, which is primarily responsible for the warpage of the part.
Abstract: The system reliability of prestressed space grid structures were using as control parameters. Branch-bound method was used to determine main failure modes. The reliability of system was calculated by PNET method. Improved genetic algorithm was used in the minimum weight optimum design of the structure system under reliability constraint. Using this method, the complex sensitivity analysis of structural systems could be avoided and made optimum design of the structure system easy. The result of an example showed that the effectiveness of the method.
Abstract: The process innovation is difficult, costly and time-consuming because it mainly depends on limited knowledge and random inspiration of individual. This paper presents a knowledge-based computer aided process innovation (KCAPI) method in order to change this situation. In this method, process knowledge is described with formal format, organized into knowledge chain. The process contradiction matrix (PCM) is used to express the relations between technical conflict items in process problem and corresponding solving theories. At last the technical conflicts can be eliminated iteratively based on PCM via knowledge chain to approach the innovation goal. The KCAPI method can implement the systematic and structured process innovation and improve the innovation efficiency and quality. A welding process innovation instance was shown to confirm this method.
Abstract: The method to analysis the strength of planetary trains’ carriers of EPB(earth pressure balance) shield machine is presented in this paper. The structure of the shield machine trains is analyzed and the 3-D solid model of the carrier is built with Pro/E. After the load on the carrier has been dealt with, the strength of carrier is calculated by means of finite element method. The results via ANSYS show that the max stress and strain on the carriers are increasing as the increasing load on it. The max stress is lying on the joint point of the carrier and planetary gear shaft because of the bending deformation of the shaft.
Abstract: Electric Power Steering (EPS) is a full electric system, which reduces the amount of steering effort by directly applying the output from an electric motor to the steering system. This research aims at developing EPS boost curve embody into the assist characteristics, improving steer portability and stability. A model for the EPS system has been established, including full vehicle mechanical system, EPS mechanical system, and EPS electric control system. Based on this model, a straight line boost curve was designed and evaluated in this environment to improve the performance of EPS system. Results showed that EPS system with the designed boost curve improved light steering feeling and increased vehicle’s steering stability, and can meet the requirements of steering performance.
Abstract: This paper introduces combining address space transformation strategy with lock strategy to maintain the consistency of both simple objects and complex objects in replicated CAD environments. This combination adapts AST strategy from group editor field to CAD environment, gurantees the high concurrency of the replicated architure, and provides relatively effective strategy to process complex objects. The combination process of AST and Lock strategy is also decribed in detail in the paper.
Abstract: With its broad application field, the injection mold has an important position in the mold industry. The key technologies of injection mold parametric design are studied deeply in this paper, and the injection mold rapid design system is developed finally. The rapid design system has friendly and convenient human-machine interface, can improve the design efficiency of injection mold greatly.
Abstract: Piston is one of the most stressed components of an engine. In this paper, a 1/2 3-D solid model of a new designed piston was built by using ANSYS software. The stable stress distribution and the deformation under the thermo-mechanical coupling condition were firstly calculated. Calculating results indicates that the maximum stress concentration is at the upper end of piston pin boss inner hole, and is mainly caused by the peak pressure of the fuel gas. Then the finite element dynamic analysis was conducted based on the mechanical fatigue testing method, and the mechanical fatigue life-span was calculated. All these work indicate that the design of the piton is reasonable.