Applied Mechanics and Materials Vols. 184-185

Abstract: The forming process of a typical cylinder part is simulated by the platform of Dynaform. The influence of blank holder force (BHF), punching speed and clearance between punch and die on the quality of forming part is assessed by the orthogonal experimental method. The value of BHF of 20KN, punching speed of 2000mm/s and clearance between punch and die of 1.1mm which are the optimized parameters value are obtained.

Abstract: The three-dimension flow field and the separation efficiency of the inclined cut-in double-inlet cyclone were simulated numerically with Reynolds Stress Model (RSM). Numerical results show that the flow field nonsymmetry is improved in the inclined cut-in double-inlet cyclone and the swirl in the flow field was decreased greatly compared to that in the single-inlet cyclone. With the increase of inclined angle, both the tangential velocity and the axial velocity first increase and then decrease, reaching a peak at inclined 12 ° angle and at inclined 10 ° angle, respectively. The pressure drop in the inclined cut-in double-inlet cyclone increases first and then decreases with the increase of inclined angle, reaching a maximum far lower than that in the single-inlet cyclone, while the change of the radial velocity is not obvious. The separation efficiency of the inclined cut-in double-inlet cyclone could be effectively improved and the optimum inclined angle is 10 °.

Abstract: The transient airflow movement has tremendous effects on aerosol deposition in human airways． The understanding of the characteristics of the transient airflow movement in human airways plays a very important role in analyzing the aerosol deposition patterns．Computational fluid dynamics(CFD)was used to simulate the transient airflow movement in generations G1-G3 of real human airways model under light activity conditions，the transient airflow patterns in the middle plane and cross sections of the airways were discussed．The results showed that in the subglottic of jet of air in the trachea front wall is formed in the air, the air at around 9.96 m/s, in trachea rear form flow separation phenomenon, along with the increase of the distance with the subglottic, tracheal inside and outside wall airflow velocity difference gradually decreased, but before the trachea wall flow speed or to be higher than the back wall of the air speed; expiratory flow into the bronchial, endobronchial forming centre air in the air distribution of higher status, level 2 level 3 endobronchial air speed the most about 2.71 m/s,.In the bronchial bifurcate place, airflow happen intersection phenomenon, intersection cause at the center of the low speed area formed bifurcation, and join the level of airflow bronchial produce temporary two air at high speed.

Abstract: In this paper, an ultrasonic transducer is designed and optimized in order to reduce the error of resonance frequency and maximize the amplitude of the radiating tip. In order to get the basic dimensions of an ultrasonic transducer easily, resonance frequency equations are derived by using the traditional analytic method. Using ANSYS FEM software, we analyzed the vibration model of the transducer, including Modal Analysis and Harmonic Response Analysis. Studied how the length of two resonance rods affects the resonance frequency. By optimizing the dimensions of the ultrasonic transducer, the error of resonance frequency is reduced to 0.03%; the amplitude of the vibrating tip is up to 6.20μm. The optimal results show that the transducer designed in this paper has superior performance parameters and meets the requirements of machining.

Abstract: The finite element model of worktable system is created and modal analysis is made with ANSYS Workbench by taking DVG850 high-speed vertical machining center worktable system for example. We make modal analysis of single-screw strength general reinforcement worktable system and get the natural frequency and the vibration mode.Then in order to improve the system's natural frequency, the scheme of dual-screw worktable system is put forward. Also natural frequency and vibration mode is got. Finally, it is proved that the performance of dual-screw worktable system is significantly better than the single-screw one. This provides a reliable reference for further study on dynamic analysis of worktable system.

Abstract: According to the problem that serious wear tire occurring in the process of producing a small number of certain urban buses, the paper applied adams software to build a virtual prototype topologic model based on former independent air suspension, and then the paper made a simulation analysis of the independent air suspension kinematics, to optimize the absolute value of the front wheel track and the absolute value of wheelbase change. Finally, the tests demonstrate that the optimization design method worths promoting

Abstract: A Control Moment Gyroscopes (CMG) is a torque generator for attitude control of a high resolution and high agility satellite without any increase in power, mass or volume. In this paper, a new support structure of the CMG is proposed. According to the configuration idea of the CMGs, the original design model of the support structure is established. Furthermore, the topology optimization is performed by the FEM software ANSYS and after that came up with a suitable layout of the support structure of the CMG. Based on the optimized design results, the 3D models of the CMG and its support structure are established by the 3D design software Pro/E. Frequency of the assembly is analyzed and calculated. Finally, took the launch dynamics environments into consideration, the vibration testing are carried out to verify the rationality of the new design structure.

Abstract: Abstract：Dynamic Modeling of the electric vehicle with motorized wheels (EVMW) is different from the conventional one. Cruise is more and more widely used in the field of vehicle performance omputing. Its calculation results are so precise, it is convenient to use and easy to achieve the integration of control strategies and vehicle simulation. In this paper, a simulation model of EVMW is built by cruise. It is used to verify the matching parameters of EVMW, and calculate the vehicle power and energy consumption rate. The results show that the powertrain parameters meet the vehicle driving range requirements

Abstract: In the traditional screw compressor rotors profile generation method, the process of cockamamie parameters adjustment and confirmatory will take a long time, so that the modified results can’t be estimated in advance. Based on freeform curve, two rotor profiles generation methods are presented in this paper. One method is positive, and the female and male rotor profiles are acquired by every profile segment defined with freeform curve; another one is reverse, and the rotor profiles are derived through the meshing line. The rotor profiles are fitted by freeform curve and the shape of rotor profile can be adjusted by moving the control points. Finally, the two methods are used to developed a system for designing quickly the rotor profiles.

Abstract: CA6140 is the most widely used kind of ordinary horizontal lathes in a factory workshop. This paper, with the aid of Pro / E software and its related functions, visually displays the structure of Lathe CA6140’s main components, dynamically simulates assembly and disassembly processes of its typical mechanism, and thereby realizes its non-damage dynamic simulation assembly and disassembly, creates the mode of combining actual and virtual dynamic assembly and disassembly and realizes the optimization of its assembly and disassembling actions.