Papers by Author: Xiao Xiong Jin

Abstract: The width of band gap is calculated with lumped mass method in order to study the wave propagation of longitudinal and transverse elastic wave of one-dimensional phononic crystal. The starting and terminating frequency is analyzed by changing the filling rate, the density difference of two materials, cross-section height ratio, and the Young's modulus of the scatter.

Abstract: Powertrain mounting system of a Hybrid Electrical Vehicle (HEV) is analyzed and researched, the expression of energy distribution matrix and that of mounting reaction force are derived, and mathematical model of the system is established in Matlab. Correctness of the model established is tested and verified through model establishing for simulation and calculation in ADAMS. Features of Hybrid Genetic Algorithm (HGA) for multiobjective optimization are analyzed and researched, model for calculation of multiobjective optimization using Hybrid Genetic Algorithm is established, targets for optimization of the system are determined, and optimization is executed based on the mounting stiffness parameters. The result that the system is optimized apparently by Hybrid Genetic Algorithm is revealed through contrast of the energy distribution matrix and mounting reaction force of pre and post-optimization.

Abstract: The theory of tire wear computation is researched, and steady state transfer analysis and steady state rolling slippage are analyzed and deduced; the uniform wear rate of discrete node on the tire tread pattern is induced based on adhesive wear mechanism. Tire body model and tread pattern model are established by using Neo-Hooken constitutive model and linear elastic model, and the whole tire model is formed. Tire wear simulation analysis is preceded with combination of Abaqus Arbitary Lagrangian and Eulerian (ALE) method and the user subroutine programmed according to tire wear computation model. Tire wear of different mileage under free rolling state, tire wear under breaking condition and driving condition are compared, and slip angle, load and tire pressure’s impact on tire wear are analyzed.

Abstract: Automotive low frequency noise is difficult to control in a traditional way. Locally resonant phononic crystals (PCs) can forbid the propagation of certain frequency. This PCs’ structure also can be fabricated to apply in automotive noise control. The simulation method is applied to establish the model of two-dimensional (2D) locally resonant phononic crystals in order to research the impact of the parameters on the propagation. The band gap of locally resonant phononic crystals in z mode is calculated using the simplified model.

Abstract: The path of tire pattern’s impact on interior noise and vibration was analyzed. The same type tires with six kinds of different tread pattern were selected as the investigating subjects, and the interior measuring points’ vibration and noise signals of different tires were measured under full load condition. The basic theory of Wavelet Transform (WT) and its signal reconstruction principle were researched, and 1/3 octave Morlet wavelet was induced and analyzed. The vibration and noise signals of measuring points were transformed by using 1/3 octave Morlet wavelet, distribution features of vibration and noise signals of six tires with different tread pattern were made a comparison in time domain and frequency domain, and the distinct results of different tires were achieved. The advantage of WT in the aspect of time-frequency analysis for time domain signal is revealed.

Abstract: Phononic crystal is a novel type of periodic composites which is presented near years. When the elastic wave frequency falls within its band gap of the phononic crystal, the propagation of vibration and sound are forbidden. This property provides a new research method for the control of low-frequency interior noise. MSC. Nastran simulation method is applied to compare the propagation of two-dimensional Bragg phononic crystal and the locally resonant phononic crystal. The impact of the parameters on the propagation is analyzed by using MSC.Nastran simulation method in order to fabricate the photonic crystal structure suitable for the automotive interior noise control.