Advanced Materials Research Vols. 291-294

Abstract: By means of analyzes the differences of mechanical properties between railway wagon with cold bending centre sill steel and common cold-formed steel, to study the differences resilience by different materials, final this given the forming principle and molding pass of cold bending centre sill. Analysis the stress state of the forming process of cold bending centre sill with multiAgent technology, establish corresponding Agent force model. In determining the basis of forming passes, then determining the deformation per passes and the amount of bended, furthermore realized the forming process of virtual in computer.

Abstract: Upon studying the form grinding principle of helical groove and the conjugate movement between the grinding wheel and screw rotor, the equation of their contact line is firstly derived. The problem of smoothing the profile of grinding wheel is then solved by using the point selection smoothing method which is concludes from the theory of complex curves and numerical analysis. Finally, with the help of computer, the simulation processing is done with the final result shows that this design method is reliable. It can not only reduce the time for design and the number of trial samples but also provides a 3D model which can be used in virtual test of screw rotor.

Abstract: With the development of virtual reality technology, using the VR technique to realize landscaping planning and ancient architecture reconstruction has become a hot research and application topic. In this paper, we use VR technique to restored the scene of the famous painting which named " Riverside Scene At Qingming Festival" by Mr. Zeduan Zhang who was a famous painter in Northern Song Dynasty. In construction of the 3D ancient scene model, this paper consultes and analyses many references about the building spatial form of the imperial garden in the Northern Song Dynasty, and put forward the method for constructing the 3D model of ancient architecture. The real-time roaming system is constructed based on the VR Platform Virtools. In addition, we research and implement the stereoscopic displaying in the roaming system by using the shading programming technique of Vritools. Experimental results show that our system provides a very immersive impression for the virtual exhibition of ancient scenes. The modeling method put forward in the paper provides a good reference for the construction of ancient architecture.

Abstract: A kind of method with immune ant colony algorithm (IACA) was applied for ship parts nesting problems. Graphics coding and pretreatment method of ship parts were proposed. A method of combination and filling transformed ship parts nesting problem into orthogonal rectangular nesting problem. An automatic nesting system was realized by use of remaining rectangular matching method and orthogonal approach grafting algorithm. A specific example was given according to the proposed algorithm, the nesting results prove that it is feasible for ship parts optimization nesting problem with IACA.

Abstract: In this paper, with the ANSYS, stress distribution and safety factor of connecting rod were analyzed by using 3D finite element method. The results show that the oil-hole of small end and medial surface of connecting rod shank are the exposed destructive positions at maximum compression condition. Maximum stress value is 214 MPa. Safety factor is 1.64. The oil-hole of small end and the transition location of small end are the exposed destructive positions at maximum stretch condition. Maximum stress value is 97.2MPa. Safety factor is 3.63. Based on the analysis, the structure of connecting rod is improved. Safety factor of connecting rod increase.

Abstract: Taking a nozzle jet for gas-fluid phase flow as a research object, the influences of the main structural parameters on the vacuum in the internal suction volume are analyzed. Utilizing the software FLUENT to simulate the gas-liquid two-phase flow in nozzle jet with different structural parameters, the pressure distributions are obtained and the relationship between the structural parameters and the vacuum in the suction volume is concerned. The results show that the vacuum in the suction volume of jet reaches the maximum when these structural parameters are some certain values. The research is helpful for the optimal design and performance testing of nozzle jets.

Abstract: The electric drive systems used in industrial applications require higher performance and reliability. The DC motor is used in many industrial applications requiring variable speed and load characteristics due to its ease of controllability. Microcontrollers can provide easy control of DC motor. In this research work, implementation of the ATmega8L microcontroller for speed control of DC motor fed by a DC chopper has been investigated. The chopper is driven by a high frequency PWM signal. Controlling the PWM duty cycle is equivalent to controlling the motor terminal voltage, which in turn adjusts directly the motor speed. A prototype of permanent magnet DC motor speed control system using the microcontroller is developed and tested.

Abstract: In this paper, with the ANSYS, stress distribution and safety factor of connecting rod were analyzed by using 3D finite element method. The results show that the exposed destructive position is the transition location of big end and connecting rod shank at maximum compression condition and maximum stretch condition. Maximum stress is 353MPa. Safety factor is 2.22. Maximum deformation is 0.0728mm. Based on the analysis, the structure of connecting rod is improved. Safety factor of connecting rod increase 12%.

Abstract: The movability and safety of an oil can vehicle is influenced greatly by the effect of the fixation between the chassis and the vehicle oil can. The butt-joint technology of the chassis and the vehicle oil can is studied in this article, and a new torsion-free-body is designed. The 3D model of the torsion-free-body is built in Pro/E, and the kinetics analysis of the complex stress point of the torsion-free-body is done in ADAMS, which can provide theoretic guidance for designer to optimize structure design.

Abstract: This paper introduces the structure and working principle of the eddy current retarder , the design method of the eddy current retarder is proposed: the design of structure parameters including of the rotor windings and the excitation of eddy current retarder are completed, and on this basis 3D design of the eddy current retarder is completed by using UG software.