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Aiming at the center shaft bracket sheet extension parts, its stamping calculation is simulated based on the sheet metal forming with nonlinear finite element software Dynaform. The contours varying with blank holder forces, friction coefficients and material performance parameters (sheet hardening exponent n and thick anisotropic coefficient r) are obtained by using the simulation software. The impact of the factors on the central shaft bracket parts stamping is analysised by using the contours, provide the theory to eliminate the fold and fracture in the stamping process.

The highest frequency duct is evaporation duct under marine atmospheric environment, and it is a special method of expanding the radar measuring range by using the evaporation duct to achieve the over-the-horizon detection. On what conditions to ensure the realization of the over-the-horizon radar detection is one of key problems. Many aspects, such as evaporation duct discrimination, radar working wavelength and frequency, initial launching angle and the location of radar are studied to get the necessary conditions of the over-the-horizon radar detection. The results show that the four kinds of necessary conditions must meet at the same time instead of only one certain condition, which lays a necessary foundation for the marine radar, ship radar and communication system to exert the largest effects in the evaporation duct environment.

Based on parameters and design requirements of the original LJ276M gasoline engine, using Helmholtz theory to calculate resonance frequency, intake manifold length and diameter and other structural parameters, rapid design a new resonance intake system. And then apply simulation software GT-Power to build working process model of the LJ276M Electronically Controlled Gasoline engine, and determine the final structural parameters of the intake system through the use of rapid prototyping and test verification methods. Compared with the original machine, the dynamic performance is improved significantly by the use of optimum design of the intake system.

By Means of Fluent 6.3，the paper simulated the solid-liquid two-phase flow to a type of centrifugal sewerage pump under different sand size and contain arenaceous concentration conditions, using Eulerian Mixture Model, adopting SIMPLE algorithm, k-ε-Ap turbulence model and partitioning non-structure hex grid in the area of flow passage in the pump. The paper analyzed wear characteristics in different parts of centrifugal sewage pump impeller and put forward some means to decrease attrition for impeller. The results can be as theoretical reference for the optimization design of the centrifugal sewage pumps

The noise of exhaust muffler is one of the key factors of the noise of the whole car. As a key member in reducing the exhaust noise, its performance directly influence the smoothness of the car. By establishment of simulation model of coupling of engine working process and muffler the plug-in loss and pressure loss are obtained. The result of simulation calculation is basically the same as that of actual test. The measures to optimize the structure of the muffler proposed based on the study have achieved relatively satisfactory effect.

Using GT-Power software to establish the simulation model of the working process of an engine coupled with the muffler, insertion loss and pressure loss are obtained, simulation results are consistent with the experimental results, which verifies the correctness of simulation model.Therefore, it is important to shorten the vehicle development cycle and reduce cost.

By Means of Fluent 6.3，the paper simulated the solid-liquid two-phase flow to a centrifugal sewerage pump，using Eulerian Mixture Model under different working condition and different particle size. The simulation draws some conclusion on distributive rules of solid particle inside impeller passage. The results for this simulation were as following: Distributive rules of solid particle inside impeller passage mainly relate to particle size. Meanwhile，the volume fraction of particles and operation condition have influence on distributive rules of solid particle. The simulated results can explain commendably that attrition took place inside pump passage when pump transported solid-liquid two-phase flow. Meanwhile，the simulated results have reference price to improve the design for pump and performance of pump.