Advanced Materials Research Vols. 605-607

Abstract: Through a Transmission bench test of a certain automobile Drive axle Assembly ,the abnormal vibration in Rear axle can be found. This paper establishes three demensions modle and Finite element model of the Rear Drive axle Assembly and calculates the modal of the Assembly and Axle housing respectively. It can be found that the frequency of the abnormal vibration in the Rear axle Bench test Coincides with the frequence of the Assembly First-order bending.It presents that it is the Assembly Resonance that leads to the abnormal vibration of Rear axle,not just Axle housing Resonance

Abstract: The non-linear dynamic responses with one degree are studied and solved by the multiple-scale method and Newton-Raphson method.The prime resonance vibrations are discussed.It is analyzed that the values of external excitation,the internal damping of the shaft and the depth of the crack have effect on the amplitude frequency response curves.

Abstract: For enclosure noise reduction, limited discrete distributed control is an ideal choice when it is difficult to understand sound-structure coupling characteristics accurately. An enclosure medel of two flexible plates is established in this paper. Two secondary control channels are constructed by applying distributed force on flexible plate. In the basis of control problem decomposition a multi-agent system (MAS) structure is established and the coordination relationship between agents is regulated. The simulaition resultes show the Active Structure Acoustic Control based on MAS is effective. The MAS control method improves the extension of noise control system and can be used in “plug-and–play” control field to realize noise reduction. MAS is a better effective tool to realize the divide-and-conquer approach in enclosure noise control field.

Abstract: Using orthogonal experimental design method structure parameters of work piece for muffler element with inserted tube are determined. Flow noise regeneration of them is measured on the self development test bench. Relationship model on total sound power of flow regeneration noise and structure parameter and flow velocity is established utilizing Multiple linear regression method, model parameters are solved making use of hyper static least square method. Significance test of the model is performed, the law of total sound power level for muffler element flow regeneration noise changing with the parameters is discussed. Result shows that the established models is all highly significant under 0.01 levels, and inserted length of outlet tube and inn-diameter of inlet tube have higher effect on the flow generation noise, and decreasing the inserted length and the inn-diameter are in favor of reducing flow generation noise. But inserted length of inlet tube and expansion ratio have little effect on the flow generation noise.

Abstract: ADAMS was used to establish the dynamics simulation model of a truck vehicle vibration system, while the engine, drive shaft and tire excitations were added to the model. For nonlinear characteristics of rubber mounting components stiffness and damping, input was conducted by the use of interpolation function SPLINE. Through the comparison of road tests and simulation results, the model reliability was verified and simulation analysis was conducted on this basis. The results show that reasonable selection and matching of powertrain mounting stiffness, mounting position could effectively improve the performance of vehicle vibration system.

Abstract: Engagement between gear teeth with confriction has been analyzed aim at low speed and heavy transmission mode of spur gear in aerogenerator gearbox. Nonlinear relation between parameters such as confriction, normal pressure, number of teeth, ratio of transmission, and thickness of fluid film has been deduced by using the theory of elasto-hydrodynamic lubrication (EHL) and gear mesh. Numerical calculation of these equations has been made progress by using MATLAB software under the premise of no analytical solution. The efficiency of each point on line of action has been received. And then the influence of confriction in intertooth space to transmission efficiency under EHL has been analyzed. The results can be provided as argument and numerical value reference for optimization of the gearbox lectotype in areogenerator to make the efficiency maximized, and for further research on transmission efficiency of planet gear train.

Abstract: Vibration analysis(VA) is a very important method in the industry inspection application. Based on ISO10816, the severity level, certainty rating, the total risk rating matrix and the risk assessment index were proposed in the paper. Based on the testing samplings in a certain company and the assessment system established above, the VA analysis can be conducted and it is a good method for applying the predictive maintenance in the plant.

Abstract: In order to research the influence of the flexible car body on the vehicle system dynamic performance and to achieve the reasonable match between high speed and lightweight，it is necessary to build vehicle system dynamic model with the rigid car body replaced by the flexible car body. Due to the lower structure natural vibration frequency of car body, the influence of carbody flexibility on vehicle system dynamic performance is more influential. The influences of structural vibration of car body on vehicle system dynamics performance were studied by finite element analysis (FEA) method and multi-body system (MBS) dynamics theory. Rigid-flexible coupled vehicle system dynamic models were built up and the car body key location’s vibration was analyzed through vibration transmission chain. The results show that the influences of high speed carbody structure vibration on vehicle system dynamics performance are distinguished especially in the domain of car body natural vibration frequency.

Abstract: Based on multi-body dynamics theory and the Lagrange equation， the rigid-flexible coupling dynamical equations of the Coal sampling arm was deduced.The rigid-flexible coupling mode is established by combining with Pro/E, ANSYS and ADAMS, and the model curve is gotten by simulation. The simulation results indicate that rigid-flexible coupling modeling is more actual and it is necessary to consider the flexible deformation of all arms when the sampling arm system is researched. The results in this paper presents the theoretical foundation for the sampling arm dynamical analysis and structure optimization.

Abstract: The model of eccentric shaft of caster vibration device is built by finite element software ANSYS, and bearings are regarded as rigid constraints and elastic constraints.Firstly, regarding the bearings as rigid constraints, the nodes on the parts of eccentric shaft, which match with bearing,are exerted full constraints. Secondly, regarding bearings as elastic constraints, spring, which is built by elastic element combination 14, are used to replace the bearings. In addition, the full constraints are exerted on the one side of spring,and axial constraint are exerted on the other side. Afterwards make the modal analysis of eccentric shaft.Solve and extract the first six natural frequency and modal shape.Watch and analyse the breaking formal of eccentric shaft as it is in different mode. The basis are settled for instantaneous and harmonic analysis.