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In order to improve the lubrication condition of high pair contact parts in point contact，the lubrication oil film in Hertz contact zone was studied. Coupled with contact mechanics and hydrodynamic lubrication equations，the multigrid method and Fortran language programming were used to solve the equations of EHL of isothermal point contact，and the curves of film thickness and pressure with different ellipticity Ke，load w，entrainment velocity u and viscosity ^0 were obtained. By studying the position of minimum film thickness and secondary pressure peak and the change degree of film thickness and pressure in the process of changing of film thickness and pressure， the factors affecting the change law of oil film in Hertz contact zone were obtained and analyzed. The results indicate that the contact ellipse changes with the change of ellipticity，load，entrainment velocity and viscosity，and the change of contact ellipse affects the film thickness and pressure of lubrication oil in varying degrees. In a certain range，increasing ellipticity，entrainment velocity and viscosity and reducing load are beneficial to improving lubrication performance. [ABSTRACT FROM AUTHOR]

Aiming at the problem of how the waterjet propulsor affects the flow fields and velocities of the inlet ducts with different lengths and pipe diameters，the 3D models of the waterjet propulsors were established. The computational fluid mechanics (CFD) technology was used to simulate the flow fields of " boat + inlet channel + waterjet propulsor" with 1 time，4times，8times of the lengths and 1. 6times， 2 times of the diameters repectively. Then the velocity nephograms of non - uniformity of the outlet flow field in the inlet duct，the cavitation nephograms of the blade suction surface and the velocity nephograms of the nozzle were obtained. The results indicate that the non - uniformity of the outlet flow field，blade cavitation and nozzle velocity is affected little by the length of the inlet duct. However，it is affected more by the diameters of the inlet duct. To improve the adaptability of the inlet duct in working conditions，its diameter should be taken into consideration for its optimization. [ABSTRACT FROM AUTHOR]

Ｉｎ ｏｒｄｅｒ ｔｏ ｉｍｐｒｏｖｅ ｔｈｅ ｌｕｂｒｉｃａｔｉｏｎ ｃｏｎｄｉｔｉｏｎ ｏｆ ｈｉｇｈ ｐａｉｒ ｃｏｎｔａｃｔ ｐａｒｔｓ ｉｎ ｐｏｉｎｔ ｃｏｎｔａｃｔ, ｔｈｅ ｌｕｂｒｉｃａｔｉｏｎ ｏｉｌ ｆｉｌｍ ｉｎ Ｈｅｒｔｚ ｃｏｎｔａｃｔ ｚｏｎｅ ｗａｓ ｓｔｕｄｉｅｄ. Ｃｏｕｐｌｅｄ ｗｉｔｈ ｃｏｎｔａｃｔ ｍｅｃｈａｎｉｃｓ ａｎｄ ｈｙｄｒｏｄｙｎａｍｉｃ ｌｕｂｒｉｃａｔｉｏｎ ｅｑｕａｔｉｏｎｓ, ｔｈｅ ｍｕｌｔｉｇｒｉｄ ｍｅｔｈｏｄ ａｎｄ Ｆｏｒｔｒａｎ ｌａｎｇｕａｇｅ ｐｒｏｇｒａｍｍｉｎｇ ｗｅｒｅ ｕｓｅｄ ｔｏ ｓｏｌｖｅ ｔｈｅ ｅｑｕａｔｉｏｎｓ ｏｆ ＥＨＬ ｏｆ ｉｓｏｔｈｅｒｍａｌ ｐｏｉｎｔ ｃｏｎｔａｃｔ, ａｎｄ ｔｈｅ ｃｕｒｖｅｓ ｏｆ ｆｉｌｍ ｔｈｉｃｋｎｅｓｓ ａｎｄ ｐｒｅｓｓｕｒｅ ｗｉｔｈ ｄｉｆｆｅｒｅｎｔ ｅｌｌｉｐｔｉｃｉｔｙ Ｋｅ, ｌｏａｄ ｗ, ｅｎｔｒａｉｎｍｅｎｔ ｖｅｌｏｃｉｔｙ ｕ ａｎｄ ｖｉｓｃｏｓｉｔｙ η０ ｗｅｒｅ ｏｂｔａｉｎｅｄ. Ｂｙ ｓｔｕｄｙｉｎｇ ｔｈｅ ｐｏｓｉｔｉｏｎ ｏｆ ｍｉｎｉｍｕｍ ｆｉｌｍ ｔｈｉｃｋｎｅｓｓ ａｎｄ ｓｅｃｏｎｄａｒｙ ｐｒｅｓｓｕｒｅ ｐｅａｋ ａｎｄ ｔｈｅ ｃｈａｎｇｅ ｄｅｇｒｅｅ ｏｆ ｆｉｌｍ ｔｈｉｃｋｎｅｓｓ ａｎｄ ｐｒｅｓｓｕｒｅ ｉｎ ｔｈｅ ｐｒｏｃｅｓｓ ｏｆ ｃｈａｎｇｉｎｇ ｏｆ ｆｉｌｍ ｔｈｉｃｋｎｅｓｓ ａｎｄ ｐｒｅｓｓｕｒｅ, ｔｈｅ ｆａｃｔｏｒｓ ａｆｆｅｃｔｉｎｇ ｔｈｅ ｃｈａｎｇｅ ｌａｗ ｏｆ ｏｉｌ ｆｉｌｍ ｉｎ Ｈｅｒｔｚ ｃｏｎｔａｃｔ ｚｏｎｅ ｗｅｒｅ ｏｂｔａｉｎｅｄ ａｎｄ ａｎａｌｙｚｅｄ. Ｔｈｅ ｒｅｓｕｌｔｓ ｉｎｄｉｃａｔｅ ｔｈａｔ ｔｈｅ ｃｏｎｔａｃｔ ｅｌｌｉｐｓｅ ｃｈａｎｇｅｓ ｗｉｔｈ ｔｈｅ ｃｈａｎｇｅ ｏｆ ｅｌｌｉｐｔｉｃｉｔｙ, ｌｏａｄ, ｅｎｔｒａｉｎｍｅｎｔ ｖｅｌｏｃｉｔｙ ａｎｄ ｖｉｓｃｏｓｉｔｙ, ａｎｄ ｔｈｅ ｃｈａｎｇｅ ｏｆ ｃｏｎｔａｃｔ ｅｌｌｉｐｓｅ ａｆｆｅｃｔｓ ｔｈｅ ｆｉｌｍ ｔｈｉｃｋｎｅｓｓ ａｎｄ ｐｒｅｓｓｕｒｅ ｏｆ ｌｕｂｒｉｃａｔｉｏｎ ｏｉｌ ｉｎ ｖａｒｙｉｎｇ ｄｅｇｒｅｅｓ. Ｉｎ ａ ｃｅｒｔａｉｎ ｒａｎｇｅ, ｉｎｃｒｅａｓｉｎｇ ｅｌｌｉｐｔｉｃｉｔｙ,ｅｎｔｒａｉｎｍｅｎｔ ｖｅｌｏｃｉｔｙ ａｎｄ ｖｉｓｃｏｓｉｔｙ ａｎｄ ｒｅｄｕｃｉｎｇ ｌｏａｄ ａｒｅ ｂｅｎｅｆｉｃｉａｌ ｔｏ ｉｍｐｒｏｖｉｎｇ ｌｕｂｒｉｃａｔｉｏｎ ｐｅｒｆｏｒｍａｎｃｅ. [ABSTRACT FROM AUTHOR]

Aiming at the problem of how the waterjet propulsor affects the flow fields and velocities of the inlet ducts with different lengths and pipe diameters, the 3D models of the waterjet propulsors were established. The computational fluid mechanics (CFD) technology was used to simulate the flow fields of " boat + inlet channel + waterjet propulsor" with 1 time, 4times, Stimes of the lengths and 1.6times, 2times of the diameters repectively. Then the velocity nephograms of non - uniformity of the outlet flow field in the inlet duct, the cavitation nephograms of the hlade suction surface and the velocity nephograms of the nozzle were obtained. The results indicate that the non — uniformity of the outlet flow field, hlade cavitation and nozzle velocity is affected little by the length of the inlet duct. However, it is affected more by the diameters of the inlet duct. To improve the adaptability of the inlet duct in working conditions, its diameter should he taken into consideration for its optimization. [ABSTRACT FROM AUTHOR]

Aiming at the problem of it being difficult to obtain the movement law of the tripod-ball type universal joint drive shaft assembly by traditional graphic or analytical method because of its complicated structure, its three-dimensional modeling was made and kinematic simulation analysis of the steel ball was completed by Pro/E software on the base of considering constraint relations among the links. The displacement curves, velocity curves and acceleration curves of the steel ball center were obtained when the angle between the input shaft and the intermediate shaft was 10°, 20° and 30° respectively. The simulation results show that the steel ball do approximate periodic harmonic motion along with the constant speed rotation of the input shaft. With the two joint angle increasing, the range of each motion parameter fluctuations is also bigger. The simulation result has reference significance for reasonable design of the tripod-ball type universal joint drive shaft assembly and can effectively solve the key technologies like friction, wear and lubrication in the automobile industry. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the pre-buried channel was used by the construction unit of the domestic and adopted gradually, but its theoretical research lagged behind the practical application of the project, the under construction of pre-buried channel was researched, and the finite element analysis and structural optimization were carried out. Through the bearing capacity analysis of the finite element calculation model for the pre-buried channel, the stress strain cloud maps of two kinds of loading modes of the pre-buried channel were obtained. Then based on ANSYS, the structural dimensions of the pre-buried channel were optimized. The results indicate the deformation amount and the equivalent stress of the buried channel under two loading modes, and after the size optimization, the quality is reduced by 6%, the maximum deformation value is reduced by 30%, the weight is reduced, and the bearing capacity of the pre-buried channel is improved. [ABSTRACT FROM AUTHOR]

Aiming at the direct influence of the vibration of this grip arm type anti stack mechanism to the structural stability and the quality of cone yarn as product, the vibration performance of the grip arm type anti stack mechanism was carried out, the 3D geometry entity model was established in Pro/E and modal analysis was generated by using the function of finite element analysis in ANSYS Workbench. And the natural frequency, inherent vibration mode and the deformation were gotten. The working frequency and the natural frequency were compared and analyzed about the grip arm type anti stack mechanism. Considering that there were chances to generate resonance in abnormal working state, the inherent vibration mode and the deformation were analyzed and the weak link in working of grip arm type anti stack mechanism was found. And the advice of improving was raised correspondingly. The results indicate that the working frequency is less than the minimum natural frequency,there is no chance to generate resonance in normal working state. The cylinder ingot is the most weak link while resonance happened occasionally. [ABSTRACT FROM AUTHOR]