Applied Mechanics and Materials Vols. 34-35

Abstract: To study the accurate calculation and failure mode diagnosis of supply chain, the idea that GO methodology is introduced into the reliability analysis of supply chain system is brought forward. Through analyzing detailedly every important factor leading to success of supply chain system and taking three-tier supply chain as the object, The GO model of reliability analysis of supply chain is found, which is universal. It can not only calculate reliability of supply chain system in detail, but also diagnose its failure mode and calculate its importance, which provides a way for improving and optimizing supply chain system. The example is presented to prove the method’s feasibility and validity.

Abstract: A meshless local Petrov-Galerkin method for the elastic dynamic analysis of a nonhomogeneous moderately thick plate is presented in this paper. The discretized system equation of the moderately thick plate is obtained using a locally weighted residual method. It uses a radial basis function coupled with a quadratic polynomial basis function as a trial function and a quartic spline function as a test function of the weighted residual method. The shape function has the Kronecker delta function properties, and no additional treatment to impose essential boundary conditions. In computational procedures, variations of material properties in the considered domain are modelled by adopting proper material parameters at Gauss points in integrations. Examples show that the presented method can give quite accurate results to elastic dynamic problems of the nonhomogeneous moderately thick plate.

Abstract: The crash box of vehicle plays an important role in absorbing energy during collision. However, the crashworthiness optimization problem is nonlinear which means the relationship between the response and design variables is implicit. This paper constructed a response surface model instead of original model. Meanwhile, uniform design has been taken to select sampling points uniformly. Then PSO method was used to optimize the approximate model with high precision. Finally, the optimization results show that the crashworthiness of structure has enhanced and provide a guide for practical application of crashworthiness design.

Abstract: The B pillar structure, which affects automotive roof crashworthiness, must have a perfect surrogate model to satisfy the early design demands. This work aims to explore the proper approach of simplified model construction. To create the simplified B pillar, the collapse theories of thin-walled hexagonal and channel beams under bending collapse are reviewed and applied to simulate the deforming behavior. Meanwhile, the simplified model is constructed from parallel connection of curved hexagonal and channel section beams. After distributing different rotational nonlinear springs, the same crashworthiness analyses are performed on both simplified and initial FE models to verify the simplified effects. The results demonstrate the potential of the approach and process proposed in developing the simplified model for the concept design of autobody.

Abstract: By ‘Radial Equilibrium’ principle, an equation was derived to describe the radial distribution of the throughflow velocity, by which a design approach was proposed for the twisted blade of axial microfan. This approach can take into consideration the influence of the radial gradient for the throughflow velocity at the impeller’s outlet, which is different from the traditional design approach for large fans assuming the throughflow velocity remains radially unchangeable. By this design approach, attempt was made on the design for an axial microfan by choosing different twisted powers so as to obtain different shapes of twisted blades and their respective aerodynamic performance was numerically investigated. Compared to the corresponding straight blade and the twisted blade designed by the traditional approach, this new twisted blade can not only enlarge the stable operating range but also improve the flow pressure, which contributes to the improvement of the blade’s aerodynamic performance.

Abstract: MDAM technology is a brand-new and low-cost machining technology. Based on the brief introduction of MDAM system, the generator structure and additional anode access method are in-depth studied. The results show that the cost of consumable parts can be reduced to a minimum of only 10.9% of the original design for optimized generator based on cost reduction, but have the problems of lifespan reduction and frequently replacement. Cost and efficiency are considered comprehensively in the design of final optimized generator, which not only extends the lifespan of consumable pieces about 4 times and improves machining efficiency, but also reduces the cost to only 36.4% of the original design. So it is adopted by the system. On the choice of additional anode access methods, through comprehensive comparison, the method of additional anode attaching with the nozzle directly is ascertained, which is simple and easy realized, and reduces the damage to the surface and sub-surface during the machining of ceramics and other brittle materials. The results lay a solid foundation for further technology promotion.

Abstract: Electromagnetic gear realize non-touching driving technology, which is non-friction and non- lubrication. Based on the FEM static analysis, creating torsional vibration dynamic model for the electromagnetic gear system with the theory and method of mechanical vibration to makes research on the dynamic performance parameter. The system makes motion stimulation by utilizing the Simulink module of MATLAB. Then, a conclusion is made through the theoretical analysis. The analysis provides some reference for the futher study of the dynamic characteristics of the magnetic gear driving system.

Abstract: The interaction between a dislocation and circular inhomogeneity in 1D hexagonal quasicrystals is investigated. By using the complex potential method, explicit solutions of complex potentials are obtained. The image force acting on the dislocation are also derived. The results show that the interface attracts the dislocation inside both the matrix and the inhomogeneity under most condition. The attraction increase with the increase of the elastic constant of phason field and the phonon-phason coupling elastic constant.

Abstract: Thermal paints, as a kind of temperature sensor, provided a non-intrusive method for surface temperature measurement. Based on chromaticity theory, the system described in this paper realized thermal paints temperature intelligent interpretation with digital image processing and database technology. The system overcome the effects of subjective interpretation, environment light and human color discrimination ability and made the analysis more accurate and consistent than manual interpretation. The digital image acquisition system was described in detail. Cubic spline interpolation algorithm was adopted to process the data in the L*a*b* color space. The system had been applied to measure the surface temperature of aero-engine combustor. The results showed that the system can greatly improve the accuracy of temperature-recognition.

Abstract: The discharge flow ripple is a crucial criterion for evaluating the piston pump. This research examines the discharge flow ripple of axial piston pump with conical cylinder block by developing a comprehensive mathematical model based upon the Bernoulli equation and the continuity equation. The novel aspect of this research is that it includes the analysis of cylinder block cone angle. From the results of this research, it can be concluded that cylinder block cone angle has a significant impact on the discharge flow ripple, and utilizing a conical cylinder block design is more feasible than cylindrical cylinder block from a flow ripple point of view. This conclusion can be used to guide the up-front design for the variable displacement pump.