Advanced Materials Research Vols. 308-310

Abstract: This paper describes the multi-sensor of the data acquisition and signal analyzing based on the development of virtual instrument. It sets up a virtual instrumentation with the function of data acquisition and signal analysis, based on computer, temperature sensor, displacement sensor, PCI data acquisition card, and software of LabVIEW8.5 .The data acquisition, preprocessing, displaying, storage and data playback are integrated in this platform, forming an easy-to-use temperature and thermal error detection system.

Abstract: The results reported in this paper pertain to the simulation of high speed hard turning when using the finite element method. In recent years high speed hard turning has emerged as a very advantageous machining process for cutting hardened steels. Among the advantages of this modern turning operation are final product quality, reduced machining time, lower cost and environmentally friendly characteristics. For the finite element modelling a commercial programme, namely the Third Wave Systems AdvantEdge, was used. This programme is specially designed for simulating cutting operations, offering to the user many designing and analysis tools. In the present analysis orthogonal cutting models are proposed, taking several processing parameters into account; the models are validated with experimental results from the relevant literature and discussed. Additionally, oblique cutting models of high speed hard turning are constructed and discussed. From the reported results useful conclusions may be drawn and it can be stated that the proposed models can be used for industrial application.

Abstract: Based on the special-shaped spring assembly of thermostat, a corresponding pickup fixture can be designed to ensure parts in a unique state in displacement process. The digital position control and machine visual identification technology are adopted for picking up part and then taking it into plastics casing riveting through the way no contact accurate positioning and control. The problem of the location of special-shaped small parts has been Solved in the thermostat assembly process. The process automation in thermostat assembly has been realized and production efficiency has been improved.

Abstract: The deicing process and practical model of aircraft on ground were introduced, and the thermal consumption was discussed. Deicing fluids deicing model of the aircraft on ground was founded based on thermal consumption. The simulation results indicated that the proposed model was effective to analyze and simulate the aircraft on ground deicing process.

Abstract: In order to improve the Remote Operated Vehicle (ROV) into a reliable and maintainable one, this paper has presented a fault tolerance control system structure. Its surface platform includes fault diagnosis and tolerance modules. In fault diagnosis module, a second order sliding mode observer has been built on the basis of its dynamic model, so as to diagnose the thrusters’ conditions through the residue of command quantity. Coresponding with its thrusters’ position, a force allocation model has been established to realize fault tolerable control. Based on duality priciple, the energy-like function concerning ROV control is established. On the basis of the energy-like function, the recurrent strategy has been deduced for thrust allocation when some of thrusters are found failure. Simulations and experiments have been made to verify and analyse the control system structure. They have proved the SY-II control architecture is a reliable control system, it can detect the thruster fault precisely, realize fault tolerable control.

Abstract: In this paper, the hazards of hydraulic pipeline system vibration and noise were introduced, the causes of vibration and noise of hydraulic pump circuit were analyzed and its frequency components were discussed. A wave filter of structure resonator based on Fluid-structure coupling vibration is designed and manufactured according to the principle of gas muffler. The differential equation of rectangular plate transverse free vibration characteristics was established, the coupling vibration resonance frequency of filter structure vibration body was obtained about 218Hz by solving differential equation according to the Rayleigh - Ritz method. The hydraulic pump flow pulsation frequency was adjusted respectively 215.55 Hz and 197.4 Hz through frequency conversion motor adjustment, and then comparative experiments were tested on the hydraulic system pressure fluctuation test experimental platform. Experiments show that, when the inherent resonance frequency of filter structural vibration body was approached the hydraulic system frequency, system pulse energy would be effectively attenuated, system pressure fluctuations would be greatly reduced and pulse rate was dropped from 3.65％to 0.28％. The attenuation of the effects of pressure pulsations was validated through experimental research, but also its defects that the filter has frequency selectivity and band narrow were founded The later research direction was put forward and new technology for hydraulic system vibration control was provided.

Abstract: According to the lever moment equilibrium, the thrust test is performed for a flat micro convergent-divergent micro nozzle with 11.72 geometry expansion ratios. During the test process, since the distances between the Piezoelectric sensors point and the bearing point are much larger than the distance between the nozzle and the bearing point, thus the thrust signal is amplified. Compared with the test results, the FLUENT6.1 software is also applied to compute steady two-dimensional and three-dimensional Navier-stokes equations for numerical results by parallel computing. The numerical results and test results show that： for the flat micro nozzle with small ratio of throat depth and width, three-dimensional wall effects are not negligible. Three-dimensional numerical results agree well with the test results while there are large differences between two-dimensional numerical results and test results. With the throat Renaults being increased, the corresponding differences between two-dimensional numerical results and test results decreased accordingly

Abstract: Electromagnetic metallurgy is an advanced subject of the production technological research in metallurgical industry. Magnetic floating smelting has already been successfully applied to producing hyperpure metal. No report on using magnetic floating method to continuously cast molten metal into near net shape waste heat processing billet along horizontal direction by one step on line. This article discusses the research and development state and the application prospect of the new technology.

Abstract: It has been seen that Cylindrical Type Instantaneous Safety Gear, which is one of the most important element of an elevator system, during safety gear operation is being exposed to high stresses and brake accelerations. The stress and deformation distribution of a cylindrical type safety gear’s brake block was investigated using finite elements and experimental methods. Results found with FEM by using ABAQUS/CAE software were compared to experimental results. It is clearly seen that the element type and boundary conditions used in finite element modelling give satisfactory results.

Abstract: Numerical method using HI and HOH meshing combined B - L turbulent model and S - A turbulent model separately based on the Rotor 37 compressor Rotor was applied to the steady flow. results on pressure characteristic curve, stall point forecast etc were compared with related experimental data. This paper discussed calculation precision influenced by the turbulence model and numerical computation grid. This numerical investigation was basis for subsequent compressor internal flow field study.