Applied Mechanics and Materials Vols. 246-247

Abstract: To study the performance of steel at elevated temperatures, the stress and deformation of steel beam were analyzed under high temperature in this paper. During the analysis, the properties of steel material must be defined firstly, which are the decisive factor affecting the carrying capacity of steel beam. The mechanical and physical properties of steel at high temperatures were accessed accordance to the provisions of the European specification in analysis. The finite element program ANSYS was used to analyze the constraints steel beam, which subjected to the uniformly line loads, then the steel beam was heated up continuously, and the mechanical properties and deformation of the steel beam was analyzed at different temperatures. The regularity of mid-span deflection changing with temperature was concluded, so as the variation of axial stress at both ends of the steel beam.

Abstract: The brush with universal motor in the existing drum washing machines features easy-to-wear, poor reliability and low efficiency. In this paper, a new washing machine with universal motor is introduced. In this product, the technical performance indexes of the universal motor is improved, production cost is reduced, and also the service life is longer, because the lamination accuracy and optimization coiling method improving rotor's lamination and the process control of low noise, low vibration, and abnormal-sound-free of the motor in high rotation speed are applied. Experiment indicates that this product features low noise and high overload ability, and its technical reliability, efficiency and noise are satisfactory.

Abstract: A general method for calculating contact fatigue strength of Mine helical cylindrical gear was studied in this paper. Both the Solid model and finite element model were created in ANSYS. Based on the fatigue analysis module of the ANSYS Workbench, The contact fatigue strengths of the helical cylindrical gear pair were calculated, and corresponding contact fatigue lives and safety factors of two gears in any meshing position were obtained and shown in contour map. A simulation calculation for a pair of mine helical cylindrical gears was carried out. Simulation results show that calculation of the contact fatigue strength of helical cylindrical gear by this method is more scientific and reasonable than traditional empirical method.

Abstract: Both the attenuation performance and the aerodynamic performance should be carefully considered in the muffler design of automobiles. Aim to improve the exhaust-muffler properties of a hybrid car, a design work has been done and introduced in the paper. Firstly, the volume analysis method was utilized to give a rough estimation. Then, the GT-Power software was employed to construct the coupled simulation models of the process of acoustic performance and engine running, by which the insertion loss analysis and the exhaust back pressure difference analysis were completed. By combined the simulation with the experiment analysis, the acoustics performance and air dynamic characteristics of each model was obtained, and it provides the theoretical fundament for the improved design.

Abstract: A kind of calculation model of 3D space transformation is introduced, which is applicable to the monocular vision of robot manipulator, and the three-dimensional space plane mapping problem of image plane to the actual horizontal plane of monocular vision has been solved. It transforms the imaging coordinate system of target in monocular vision into the world coordinate system of the manipulator, so as to calculate the relative position of targets and the manipulator. The algorithm has better accuracy and reliability, which is proved by contrasting and testing the calculation result of object coordinate system transformed to the actual position coordinates to the sampling points in embedded platform.

Abstract: The riveting quality has an important influence on the performance of the aircraft structure. The amount of interference can be an important indicator of the quality of riveted structure. The relationship between the clearance between rivet and hole and uniformity of interference is researched theoretically and experimentally against the aviation panel riveted structure. First, the riveting deformation stages are divided, and the deformation law is theoretically analyzed. The test scheme is designed and carried out based on the actual situation. Then, the experiment result is monitored and compensated. Finally, the relationship between the clearance between rivet and hole and uniformity of interfere is given out with the slope of interference as the uniform evaluation index.

Abstract: To improve the efficiency of heat utilization on domestic gas-cooker, the reasons of low-heat efficiency and the factors which influence the measurement of heat efficiency were analyzed in this paper. A new energy-saving apparatus of domestic gas-cooker is developed by the preparation of special heat-insulating material, heat reflecting paint and the use of multilayer, scraggly and crossed abdominal fire rings. Meanwhile, the special designs with resort chambers of flame and the micropores can contribute to the circulation of combustion-supporting hot air. It has also demonstrated that the design increased evidently the detention and reflection of heat. Test results show that the efficiency of gas combustion and the heat utilization were effectively improved.

Abstract: According to the non-stationarity characteristics of the vibration signals from reciprocating machinery,a fault diagnosis method based on empirical mode decomposition,Lempel-Ziv complexity and support vector machine(SVM) is proposed.Firstly,the vibration signals were decomposed into a finite number of intrinsic mode functions(IMF), then choosed some IMF components with the criteria of mutual correlation coefficient between IMF components and denoised signal.Thirdly the complexity feature of each IMF component was calculated as faulty eigenvector and served as input of SVM classifier so that the faults of machine are classified.Practical experimental data is used to verify this method,and the diagnosis results and comparative tests fully validate its effectiveness and generalization abilities.

Abstract: The FC2000 automatic engine test system for control and measuring the engine speed, torque, power, fuel consumption, temperature, pressure, and flow rate of different kinds of parameters. Different kinds of sensor output signal, focused on CAN intelligent module regulate into standard digital signal, through the bus network for transmission, facilitate the centralized management. The engine was burning, E15 E20, the mixed fuel, as a mixing of acetate ethylene glycol proportion of the increase, the economy improved. In 2200 RPM, 2800 RPM, 3600 RPM load characteristics, with a acetate ethylene glycol mixing ratio increases, CO emissions in the small and medium-sized load conditions gradually increase in big load conditions gradually improve.