Applied Mechanics and Materials Vols. 52-54

Abstract: Multi-link independent suspension is built according to the hard point parameters of a car. According to the multi-body dynamics and Suspension Kinematics theory, with the working condition of wheel travel and braking, the suspension performance is analyzed and discussed by changing rubber bushing stiffness of under control arm. The conclusion is drawn that axial stiffness of rubber bushing has almost no effect on the suspension performance, but radical stiffness has a little effect and torsion stiffness has the biggest effect on the suspension performance of these three parameters.

Abstract: In recent years, a lot of studies on brake of car aims to reduce stress, vibration and noise of the brake on vehicle. In this paper presents a sensitivity analysis of pressure and friction coefficient effect to stress of disc brake. Base on this result, an optimization for brake by stress constraints was performed. The results are shown that the contact area between disc brake and pad also it’s stress and pressure. Studies also have shown relationships between pressure, friction coefficient and stress of brake. After that, we optimize the model of disc brake by stress constraints to obtain the new model better. This is a pre study for studies on dynamic and vibration of disc brake.

Abstract: The problem of tracking for second-order dynamical systems subject to disturbance input is considered by using a complete parametric design approach. The goal of this problem is to design a controller such that the output of the controlled system robustly asymptotically tracks the output of the reference model, and the transfer function from the exogenous disturbance to the tracking error meets a prescribed norm upper bound constraint. Based on the complete parametric solution to a class of generalized second-order Sylvester matrix equations, complete parameterizations for all the controller gain matrices are established in terms of two set of freedom parameters. Also, based on these parametric gain matrices, the prescribed norm upper bound constraint is transformed into an equivalent constraint condition which restricts the choice of the freedom parameters. An example is utilized to show the effect of the proposed approach.

Abstract: Computation model for TNM360 wear-resistant steel quenching process is established by finite element method. Four work conditions are designed for studying the effect of different location of cooling zone on quenching plate shape. And the temperature field and stress-strain field under four work conditions are calculated through the established model. For 20mm thick steel plate, the effect of uneven cooling of the front of cooling zone on the plate shape is larger than that of the rear of cooling zone. Under different work conditions, the effect of thermal stress on plate shape is different with phase transition stress. The results of the study provide important theoretical basis to control wear-resistant steel plate shape and improve production efficiency and manufacturing yield.

Abstract: Based on Duncan-zhang nonlinear elastic model and ANSYS software, impacts on the settlement and stress of dam as well as the panel deflection are studied with different modulus of dam embankment materials and zoning of rock-fill dams. Through a variety of comparisons, the result shows that the dam settlement and the maximum deflection of panels increase as the initial elastic modulus ratio of main to secondary rock-fill rising. The ratio was much more reasonable within 1 - 2 and the dam deformation was small; 0.3 times top of the dam filled with high strength rock-fill materials might decrease settlement and panel deflection. The boundary line could be put forward to upstream appropriately to improve the utilization of soft rock with modulus ratio of main to secondary rock-fill less than 1.5 times.

Abstract: In order to collecting, analyzing and processing the shearer body’s vibration data, we use Labview for data acquisition and signal analysis. By the computer to complete a range of its functions. Instead of the traditional instruments, Labview has a better programming convenience, strong function and flexibility.

Abstract: Rapid economy development and upsurge of paper consumption cause the shortage of paper material. Waste paper recycling can solve this problem effectively. This paper analyses the status of waste paper recycling in China and abroad，also the technology development trend. According to the situation of our country, suggestions for strengthening recycling of waste paper are proposed.

Abstract: In this paper, we will extend a Volterra identification technique of nonlinear systems. In reality there exists a large class of weakly Nonlinear System which can be well defined by the first few kernels of the Volterra series. In general, Engineers believe that identifying high-order Volterra kernels is a big problem and hope for the advent of better identification techniques. However, with the extensive development of the Volterra kernels’ identification technique, the situation may improve. The formulas used to calculate kernels up to the third-order are given.

Abstract: The effectiveness and actualities of mechanical system virtual prototyping software were summarized. The process from prototype to utility, commercialization and industrialization were analyzed in software engineering. The basic concept of practical improvement for a mechanical system virtual prototyping software was presented. The key points of the mathematical model, topology structure, constraint type, kinematic and dynamic simulation and data exchange were discussed by the theory of multibody system dynamics and the technique of object-oriented.

Abstract: Zirconia nanoparticles were prepared in ionic liquid BMIMBF4-water using zirconium salt (ZrOCl2•8H2O), urea as raw material by hydrothermal synthesis method. The structure and morphology of zirconia were characterized by XRD and TEM. The experimental results showed zirconia nanoparticles could be prepared at 170°C for 24 hours in a hydrothermal kettle. Its size was about 10-30nm and the particles dispersed uniformly, and had no agglomeration phenomenon.