Advanced Materials Research Vols. 299-300

Abstract: The performance of a steam ejector was simulated using FLUENT. The performance of steam ejector was studied by changing the distance between primary nozzle outlet and mixing chamber inlet (DPM) while operating pressures and other geometric parameters were not varied. The entrainment ratios of the steam ejector with different values of DPM were calculated. The optimum range of DPM was given, which is changed from 1.8 to 2 times of the throat diameter of hybrid diffuser pipe. The errors of the CFD results to the experimental results of the entrainment ratio are not more than 15%.

Abstract: Drive at Center of Gravity (DCG) Feed Principle plays an important role in suppressing the vibration and improving machining stability. But its application is very difficult while the position of gravity center changes constantly. In this paper, it is clarified that twin drive system is not exclusively optimum for solving the application of DCG, and that the choice of driving force direction is critical for reducing the vibration. Combining the method of counter balance, single drive system is proved to be valuable supplement for the design rules based on DCG. These rules are proved to be reasonable by accuracy evaluation for a die and mould machining center.

Abstract: The vibration simulation to disc vibration dryer based the virtual prototype of ADAMS. Through the analysis of the simulation results, find out the vibration displacement and angular velocity curve of vibration dryer by different installation angle of vibration motor, which can conduct dryer machine structure design and worksite debugging, and provides reference for regulation research of materials movement in dryer machine.

Abstract: Multi-way loading technology provides an efficient method to form integral triple valve parts. However, some forming defects such as cracking and folding are prone to occur, which will weaken the forming limit and quality of formed triple valves. Based on numerical simulation, taking forming load, damage, stress, strain and folding as objectives the forming limit and feasibility were studied by changing geometric dimension of billet and triple valve to be formed. The results showed that (1) for a given billet, as the inner diameter of triple valve increasing, the forming load, maximum damage value, stress and strain increased, i.e. the larger the inner diameter of triple valve the more difficult to form; (2) For triple valves with a given inner-outer diameter ration the maximum damage, maximum stress and strain values increased as triple valve outer diameter decreasing while forming load changed a little. The possibility of folding would augment with the increase of inner-outer diameter ratio d/D, when d/D≥0.8, folding occurred under the forming condition in this paper.

Abstract: The curvature characters of revolving curved surface are discussed. A list of the formulas of average curvature and Gauss curvature are made. The math model can be used to provide references to design some milling cutter.

Abstract: Reverse engineering is used to obtain mold’s numerical point cloud. The key is to get mold’s defective area and boundary’s features information. Then its original model of mold’s defective parts is built, and combined with bi-cubic B-spline to control vertex, the abutting of curves and surfaces, and value iteration technologies for integrate modeling of defect molds.Using finite element analysis and multiple technologies to analyze and amend, the model is repeated revised until a mold’s complete model is obtained.

Abstract: To achieve effective U-band integrated amplification in a cm² glass substrate, bent waveguide structure (U-bend) based on Tm³⁺ doped germanate glass substrate has been designed. Using simulated-bend method, the optimal radius for the curved structure is offered to be 2.30 cm with a bending loss coefficient of 0.054 dB/cm. For the U-bend waveguide, the evident signal gain is anticipated in the wavelength range of U-band, and the ideal internal gain is derived to be 5.77 dB at 1675 nm wavelength, which is two times higher than 2.52 dB in the straight one. Simulation results indicate that reasonable optical path design can enhance the optical gain in Tm³⁺ doped germanate glass channel waveguides considerably, which provides a feasible designing idea in realizing practical applications for U-band amplification devices.

Abstract: The designed spindle of turning center is researched. There are two groups of the spring-damper elements to simulate the bearings. The spindle is modeled to be 3D FEM parametric model, and the static analysis, model analysis and harmonic analysis are finished in ANSYS. Static stiffness, natural frequency and dynamic stiffness are calculated, the danger points are checked according to the resonance modes, and the performance of the spindle is verified to be reliable.

Abstract: When rolled heavy rail is on the cooling bed for natural cooling, the heat transfer coefficient has important effect on the bending and section sizes of cooled heavy rail. In the paper, the heat-stress couple module of ANSYS software is adopted to carry on numerical simulation on the cooling process of 60kg/m U75V heavy rail, and we obtain the change rule that heat transfer coefficient has effect on bending curvature and section sizes of cooled heavy rail. This study is of great reference value on cooling bed design and the formulation of cooling technological parameters for high speed heavy rail.

Abstract: Based on the 3D plane impact and 2D MCA numerical simulation, the 3D ANSYS/LS-DYNA software is applied to conduct numerical simulations on two kinds of impact breaking process of a glass ball, during which spallation phenomenon occur. The Von Misses stress of each node changes with the time as the result of the stress waves spreading, reflecting and overlapping within the material. The stereograms and profiles from the simulation results reveal that the stress of each node changes with the time. By comparing the simulation results of plane impact and 2D point impact, differences and similarities between these processes are illustrated in this paper, which reflects the complexity of mechanics in the processes.