Analysis on Longitudinal Cracks and Deflection of the Pre-stressed V-shape Slab Roof Structure     

YANG Hong-yuan  FAN Ze-bao  CUI Jia 《保鲜与加工》2002,(3):112-116

In this paper, the finite element method is used to analyze the behavior of the prestressed V-shape Slab Roof structure, especially the effect of temperature change on the stress of slab. The calculated results indicate that when the temperature changes, the tensile stress at the lower extreme fibers of the flange plate near rib exceeds the tensile strength of concrete subjected to the combined action of triaxial stresses and results in the longitudinal cracks of the flange plate. The deflection analysis is based on the mechanical model of the prestressed V shape slab with the longitudinal cracks. The calculated results are in general agreement with the field observations.  相似文献   

Harmonic Analysis and Suppression of High-frequency Welding Devices     

LUO Sheng-jin  DU Xiong  ZHOU Luo-wei 《保鲜与加工》2005,(2):26-31

This paper analyzes the structure and line current waveform of 3-phase AC voltage regulation circuit. As an application of 3-phase AC voltage regulation circuit, a high-frequency welding device's simulation model and harmonic analysis of line current are presented. Results of simulation are compared to field measurements. The two are in a good agreement, so this simulation model is correct. Two single-tuning filters and one second-order HPF are designed according to the device's harmonic condition. Simulation results of the circuit with filters indicate decrease of the harmonics in current of power supply, and the waveform is close to sinusoidal wave, which prove correctness of the solution to harmonics pollution.  相似文献   

Rectangular Cover System of Manifold Method and Its Auto Mesh Algorithm   总被引：2，自引：0，他引：2  

CAI Yong chang  ZHANG Xiang wei 《保鲜与加工》2001,(1):42-46

In contrast to the finite element method, another form of numerical method which is based on the using of rectangular math covers in manifold method is proposed. In this method, the element data is not a necessary in the input data files and it can be incorporated with the CAD technology conveniently. The theory and application of the method are discussed and the auto mesh algorithm of the cover system is also given in this paper. The numerical examples indicate that the method and the algorithm are accurate and effective.  相似文献   

Direct Factor Analysis With Discrete X-Ray Diffraction Patterns     

Chen Changguo Liao Bogang 《保鲜与加工》1993,(2):70-72

In this paper,we put forward a method of direct factor analysis with discrete X-ray diffraction patterns, which was supported by the experimental measurement with the mixture containing 2,3,4,5 phases respectively. The detailed discussion was also given to its principles,errors and criterion.  相似文献   

Intensity Comparative Analysis Based on Ideas Between Involute Gear and Double Involute Gear     

ZHANG Guang-hui  TAO Ling-feng  LIU Wen 《保鲜与加工》2005,(11):1-4

Modeler and simulation modules in Ideas software are used to build the finite element models on involute gear and double involute gear with accurate tooth shape, and with the same design parameters and under the same loads, finite element contact analysis has been done. At last, the contact stress and bending stress on the two types gear transmission at the different meshing positions are solved out, and comparative analysis and study have been done. At the same time, that the ladder-shape tooth on the double involute gear how to influence contact stress and bending stress is emphatically analysed. All above offer the theoretical foundation that bring the double involute gear with ladder-shape tooth into the industry.  相似文献   

Simulation and Experiment of the Forging Process of Railway Lorry Bomsster     

WANG Meng-han  CHEN Xi-hou  ZHOU Jie 《保鲜与加工》2007,(5):83-86

Bomsster is a key load-bearing part of railway lorry bogie.Because of its inherent defects casting-steel bomsster could not meet the demands of the heavy load,acceleration and security for lorry.So forging process is proposed to form it.The forming performance of forging-steel bomsster is analyzed.A forging technology is presented which realizes two forging-steel bomsster parts formed in one die.With the plastic forming simulation software DEFORM-3D,the simulation and optimization of the forming process of forging bomsster has been taken based on 3D rigid visco-plastic FEM theory.Optimized scheme has been used to direct the pilot product.The results of product's testing and application suggest that the new forging technology is feasible and the performance of the product is credibility and stabilization.The factory has realized large scale production of a series of forging-steel bomsster.Remarkable benefits of both economy and society have been achieved.  相似文献   

Spline Boundary Element Method for Calculating Three-Dimensional Electrostatic Fields     

Yun Zhengqing Tan Bangding 《保鲜与加工》1993,(5):79-84

Based on [l].this paper presents a new spline-BEM for calculating 3-D electrostatic fields,in which bi-cubic B-splines are used as basis functions. The corner problem in BEM and the extreme conditions for splines are circumvented. The numerical results presented show that the global approximation .convergence and stability of the method are satisfactory.  相似文献   

Coupled Thermo-Elastic Contact Finite Element Method and It''s Application in Gearing     

Li Runfang Li Yusheng 《保鲜与加工》1993,(1):96-101

A new finite element method is presented in this paper to analyze the thermo- elastic contact problem with heat input on meshing tooth faces. The computational model of meshing gear has been established and the frictional heat input on meshing tooth faces is estimated. In addition, 2-D finite element analysis program for this kind of problem is listed. The test and practical examples are given to show the validity and versatility of this method.  相似文献   

FINITE ELEMENT PREDICTION OF THE PERFORMANCE OF AN INSTRUCMENTED GEOTEXTILE-REINFORCED WALL     

Peng Shusheng 《保鲜与加工》1995,(3):85-95

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Application of Engineering WorkStation in Analysis of Truck Crashworthiness     

Yang Changqi 《保鲜与加工》1995,(1):81-86

This paper presents the basic equations and algorithm of vehicle crashworthinessbriefly.Take a light-truck for example,some applied problems in ustng Engineering WorkStationto analysis truck crashworthiness are discussed.A installation method of contact surface is intro-duced,Finally,a nurnerical simulation result is presented.  相似文献