Applied Mechanics and Materials Vols. 152-154

Abstract: A gear microscopic surface pitting lubrication model was established, and the oil condition of it was introduced. Based on the multi-grid method, a numerical solution of spur gear oil condition lubrication was obtained. The result show that with the provided oil film thickness increases, the film thickness of the meshing point also increases. However, when it is added to a certain degree, the film thickness will no longer change, the phenomenon is worthy of discussion. The result shows that lack oil lubrication is detrimental to the gear, but it will not be better as the amout of oil adds, there exists a critical point.

Abstract: The article aims at Shenzhen LNG bus for the engine oil change period research. We sample the vehicle new and replaced oil, test the quality indicators in determining the parameters of the engine oil, analyze the engine oil,s kinematic viscosity change rate (100 °C), flash point (closed), decreased rate of base value, acid value increment ,pentane insoluble, water, iron, copper, aluminum，silicon content and other items for determining the engine oil drain interval. Based on the results obtained reasonable drain cycle for LNG bus, come to appropriate use recommendations and repairing guidance for LNG bus, and instruct the LNG bus choose suitable engine oil drain cycle in order to extend the engine oil life.

Abstract: Twist-bend coupling is a very important way to reduce the fatigue loads for megawatt blades. This paper studied the twist-bend coupling properties of 5MW wind turbine blades using finite element method. Twist angle, flapwise bending angle and coupling parameter are given for each aspect by applying same loading condition. Simulated results show that material can greatly affect the coupling properties while the influence induced by the structure of blade can be ignored.

Abstract: Increased the machinery of spring and baffle to prevent goods falling bodies ,in order to ensure the safety of persons and goods when loading and unloading. Using UG software for designing automotive Vehicle Tailboards structure of solid modeling, using ANSYS software for mechanical analysising the floating beam, which is the important structural parts of automotive Vehicle’s Tailboards. Analysis the floating beam in different thicknesses and loads of stress, To determined the optimal combination about thickness and load of the floating beam. Above all, The main components of mechanical analysis cannot product the Vehicle’s Tailboards by ANSYS software,Which saving costs on the design and manufacture of production, shorten production cycle and improved the market competitiveness of the product.

Abstract: Gear oil pump with the circle-arc and cycloid tooth profiles is a kind of inner meshed gear pump. The research on lubricating capability of the kind of pump is very lacking, though they are widely applied for many fields. The lubricant medium film thickness was calculated and the change trends of film thickness were found, combining characteristic of pump with the arc-cycloid tooth profiles. Calculating results indicate that full film lubrication can be easily formed at meshing zone when the pump was running. This shows that meshing efficiency of this kind of gear pump was good and wear quantity was small.

Abstract: In China, the geotechnical engineering has aroused the attention of geotechnical engineers, who take it as a special research topic. In this paper, problems on artificial filling are discussed, including the environmental geotechnical engineering, the foundation and engineering practices, with corresponding solutions put forward.

Abstract: Hot judder characteristics of a ventilated disc brake system are discussed. Three dimensional finite element models of the ventilated disc, pads and pistons are created, and a fully coupled thermo-mechanical analysis of the hot judder phenomenon of the disc brake system is performed using SAMCEF. The brake dynamo test is carried out according to the high speed judder test mode. The evolution of the temperature distribution on the disc surface is described, and the hot spot generation process is investigated. The simulation results such as the maximum disc temperature, BTV are compared to the data from the dynamo test, and the reliabilities of the analysis technique and simulation model presented in this paper are verified.

Abstract: By analyzing the output procedure and theoretical calculation method of power machinery output torque, a kind of advisable simulation method to power machinery output torque was put forward. For example, the wobble plate engine dynamic simulation model was created by this method. And simulation calculation was done based on dynamic model. Result Comparison between simulation calculation and theoretical calculation shows that this method has high calculation precision and maneuverability. At last, some reference suggestions were put forward for application.

Abstract: In order to investigate the effect of material nonlinearity on the dynamic behavior of bioprosthetic heart valve, we establish the spherical, cylindrical and ellipsoidal leaflets models with the material model of Mooney-Rivlin. The mechanical behavior of bioprosthetic valve leaflet during diastolic phase is analyzed. The finite element analysis results show that the stress distributions of the ellipsoidal and spherical valve leaflets are comparatively reasonable. The ellipsoidal and spherical valve leaflets have the following advantages over the cylindrical leaflet valve, lower peak von-Mises stress, smaller stress concentration area, and relatively uniform stress distribution. This work is very helpful to manufacture reasonable shaped valvular leaflets，thus to prolong the lifetime of the bioprosthetic heart valve.

Abstract: In order to analyze the performance of a certain FSAE racing car with rear wing at different attack angles by virtual prototyping technology. The multi-body model of a FSAE racing car which takes non-linear factors into consideration was built by applying ADAMS/Car. The correctness of the model is verified by comparison with the actual experiment result. By the simulation of the air resistance and lift characteristics of the rear wing, a feasible method to building the aerodynamic characteristics of the rear wing in multi-body model was proposed. Based on these, the crosswind stability of FSAE racing car with rear wing at different attack angles was analyzed, the result shows that the effect of crosswind is reduced with the increase of the attack angle of the rear wing.