Applied Mechanics and Materials Vols. 548-549

Abstract: With the continuous deepening of the assembly process of automobile, the analysis and test technology of the production system become more important. According to a transmission company automobile speed changer production enterprise assembly process as the object, established the assembly process model, analyzed the bottleneck, imbalance, logistics transport not smooth and so on of the assembly line. Increase the production capacity of production system through analyzing and testing the model.

Abstract: This paper describes a new kind of direct-drive wave turbine, which collects wave energy and part of tide through a specially designed turbine device. We want to know the right flow rate,the maximum torque, the average power.Focusing on the use of ANSYS software for the model under different flow rates, we obtain important parameters such as torque and power. Then further analysis and research by experiment are proposed. We could draw a conclusion that the device is a low number of revolutions of the turbine, which unit capacity of up to 300W, suitable for the actual ocean wave gathering requirements .The article can provide practical guidance to optimize the design.

Abstract: Integral impeller is a key part of engine, and its 3D modeling of the blade is difficult in the impeller design, which is also an important factor that affects engine performance. Aimed at improving the poorer quality of blade surface machined by five-axis NC machining center, the smoothing methods in which curves and surfaces are accordingly divided into different pattern and direction are presented on the basis of UG. Smoothing results of the surface modeling and the quality of integral impeller blade in actual machining are increased significantly. The experiment shows that the method is convenient and effective to improve blade surface quality and meet the demand of practical engineering.

Abstract: An automatic test system of airflow performance in refrigerator transportation vehicle is proposed and constructed. The wind velocity field of loading area of empty refrigerated compartment is test in this research. The distribution characteristics of the tri-dimensional wind velocity field are analyzed. The plenty vortex areas in the back part of the recurvature area of the refrigerated compartment is beneficial to the uniformity of the temperature field, the flow fields of the loading area are obviously influenced by vortex areas and the face that the area below the return air inlet is most probably one of the temperature blind angles are concluded.

Abstract: Firstly, according to the physical makeup and the structure characteristics of landslide mass in one area, there are 6 kinds of typical hazard factors are put forward, such as mining under the ground, landslide characteristics, geological structure, and height of wave, grading angle, and rain intensity. Application of fuzzy mathematics theory, the fuzzy mathematics evaluation model on the slope stability of many factors is established. Evaluate criterion of continuous variable and discrete variable are determined based on the analysis of landslide characteristics and spatial-temporal distribution, then slope stability is evaluated, and the evaluation results are in accord with the practical situation. Finally, based on above evaluation results, Landslides Monitoring Network in mining area is established, and monitoring results proved that the landslides in the mining area are stability at present.

Abstract: In order to extract the weak fault information from complicated vibration signal of rolling element bearing, the Recursive Least-Squares (RLS) Lattice-Ladder Algorithms is introduced into the field of rolling bearing feature extraction. An adaptive feature extraction method is proposed. The RLS Lattice-Ladder algorithms and its adaptive filter property in the process of feature extraction were discussed. The rolling bearing vibration signal was refined by the RLS Lattice-Ladder filter method, and the refined vibration signal was demodulated by square envelope, then the rolling bearing’s characteristic fault frequency was identified by enveloped normalized amplitude-frequency spectrum. Simulation results show that compared with the LMS filter method, this method can identify fault frequency more quickly and more effectively.

Abstract: Four kinds of cavitations suppression schemes on the basis of cavitations theory of control valve were designed in this paper. The fluid dynamic characteristics parameters under the above schemes was obtained by using RNG k-ε turbulence model respectively, which is composed with the velocity vector of internal fluid, pressure and cavitations distribution contours of numerical simulation. The results show that the design of straight-through porous structure has a lot of advantages compared with other structures in terms of its good fluid dynamic characteristics that fluid flow is uniformly in the valve cartridge, the loss of pressure is lower, the impaction in expansion cartridge is smaller and impact noise of it can be reduced. Therefore, the straight-through porous structure could suppress the initiation and development of the cavitations.

Abstract: A polishing process is generally used for improving work surface quality through the abrasive machining scheme. In this study, a stainless steel cookware was polished by using a sisal wheel and its surface roughness was examined. A comparison of three different sisal wheels was initially made to evaluate their performance in terms of capability to achieve the required surface finish against the processing time. The polishing force, time and velocity were the three main parameters, taken into consideration in this study. The optimum condition of 61 m/s, 15 seconds and 65 N for polishing velocity, time and force was suggested, respectively. After implementing the optimum condition and comparing to the current setting, the processing time can be reduced by half.

Abstract: This paper aims at studying the effect of polishing parameters on surface roughness by using the cloth wheel polishing process. Stainless steel was used as a specimen in this study. The investigation firstly accounted for the comparison between two polishing compounds, and the best one was used to be applied in a set of experiment. The effect of spindle speed, current and polishing time on the surface roughness of stainless steel was examined, and the results showed that polishing time and current played the significant role in degree of roughness. The optimum condition under the range of parameters considered in this work was determined, whose surface roughness was about 0.0466 μm.

Abstract: An automatic wiper control system based on the adjacent capacitive used in automotive industry. Three types of capacitance sensor in different shapes (round-arrays, flower-shaped and single-ring) are designed, and their performances are simulated by using COMSOL and MATLAB under the same conditions. The results indicate the performance of the single-ring sensor is the best, and its sensitivity reaches 192.17fF/mm, which overcomes the problem of weak output. The data acquisition and conversion circuit based on digital chip AD7142 is designed to enhance the anti-interference and reduce the system cost. The experimental results prove the feasibility of the automatic wiper control system used on automatic car.