Applied Mechanics and Materials Vol. 470

Abstract: Based on the fundamental assumption of the stretch-bending straightening theory and applying the elastoplastic theory, the paper analyzes and deduces the distribution and change of stress and strain of strip in the bending springback, raising that bending unloading will increase the elongation of the neutral layer of the strip. Then, through the conditions set-up of the finite element simulation model and results of data analysis, we found the effect of different tension and bending degree on the elongation for the neutral layer of the cold strip in process of unloading, and this kind of influence is described quantitatively.

Abstract: The contribution compares the response of envelope of chosen structure to the effects of transient load. The load was caused by air blast wave due to deflagration of methane-air mixture. The paper deals with interaction of incident blast wave and envelope structure. Considering blast courses obtained from experiments, two simplified models of load were developed. Load, defined by both load functions, was applied to 3D numerical model of the structure. Calculated result values of deflections of wall elements were compared to experimentally obtained deflections.

Abstract: Because of the important influence of temperature on the process of manufacturing rubber products and in the actual production process ,the internal temperature of the product is very difficult to measure, so this paper simulated the PCP`s rubber stator injection molding process using finite element software, and detailed analysis of the temperature distribution in the case of injection molding process and injection molding after the completion of the molding, provides the theory support for the design and production process of stator improvement, to further improve the product quality and production efficiency to provide guarantee.

Abstract: The structural problem of materials, belonging to the field of material mechanics, is one of the most challenging problems for geotechnical materials. The theory of full state function for materials is a feasible method to describe the structural property of materials. Based on the analysis of structural parameters and its number in the geometric - mechanical material model, the concept of full state function for materials was introduced in this study. The full state function of structural parameters for the materials was obtained. It was found that, in the specific material analysis model, the number of the structural parameters of materials was known. The physical meaning of the corresponding material parameters was essentially the reflection of the degree of mutual influence among the directions of the structure of the material. The number of independent structural parameters represented the number of combinations which could produce influence independently among the direction of structured materials. The magnitude of the structural parameter reflected the degree of mutual influence among the structured directions. It could also be thought that the inconsistency of geometric - mechanical properties along the direction of the structured materials was reflected by the number of structural parameters, while the inconsistency degree was reflected by the magnitude of the structural parameters.

Abstract: To solve the end effect occurring in empirical mode decomposition adopted in the course of decomposition, we propose an improved method on the basis of time-sequence analysis and cosine window function. First, the ARMA (Autoregressive Moving Average) of time-varying parameter is adopted to extend signals, and thus the extended data can be smoothly connected with the original signal at the end. Second, the extended signals are processed with cosine window, so that the extended errors will exert no impact on the existing data. Finally, the signals processed as above mentioned will be decomposed with EMD to confine the end effect to the ends of the signal. The simulation and fault signal analysis prove that the proposed method can effectively reduce the impact of the end effect and be applied in rotating machinery fault diagnosis.

Abstract: In the fully mechanized coalmining face, all the main hydraulic supports have the four-bar connecting rod. The design of the four-link mechanism is an important part of the modern hydraulic support design. This paper has analyzed the hydraulic supports four-bar connecting rod design process according to the deflective mount of the top beam. Simplified support model has written kinematic and mechanical equations of the four-bar type hydraulic support. This paper has proposed a method which can design the four connecting rod of hydraulic support based on matlab and solve nonlinear equations of kinematics, and has compiled into a visual computing program. Gives an example of the design requirements, applying this procedure design and calculation parameters of the hydraulic support, and using the AutoCAD drawing to verify results, calculation results are correct. The program improves efficiency of the hydraulic support design. The application of this procedure can be repeated, variables are modified until getting a satisfactory design results.

Abstract: The lithium ion battery, thanks to their high density and high power, became promotes element for hybrid and EV vehicles. After several recent researches, it has been proved that lithium ion batteries are currently confronts a problem of temperature rise during their operation discharge, which affects the batteries performance, efficiency and reduces the life of lithium ion battery. However, this work is set to access the three dimensional analytical modeling based on Greens Function technique to study the thermal behavior of lithium-ion battery during discharge with different discharge rates (0.3C, C/2,1C, 2C,) and strategies natural convection cooling on the surface of the battery is performed.

Abstract: The paper established a composite foundation model, from top to bottom, the model is the backplane of structure. Using FLAC3D4.0 for numerical simulation, by changing the pile tip in upper, middle and lower in of soil underlying grid , analyze the settlement of the pile and pile axial force with the variation of mesh density and pile length, Therefore recommended that simulate the actual project will pile grid, but the appropriate grid density mainly depends on the measured value or experimental values of simulate project.

Abstract: The two-dimensional O-ring seal nonlinear axisymmetric finite element model are established which is used for swinging hydraulic cylinder. Some factors influencing rubber O-ring sealing performance were taken into account, such as rotating shaft diameter, O-ring seal section diameter. The results indicate that when medium pressure is zero, the two factors influence Von Mises and maximum contact stress of sealing face greatly. Under medium pressure (P=10Mpa), the two factors have a little influence to Von Mises and maximum contact stress.

Abstract: A new kind of self-healing composite gear, namely the short glass fiber reinforced nylon 6 composite gear with 3.5wt% microcapsules, is studied in this paper. Its 3D model is built through the parameterized modeling function of Pro/E software, and then its stress distribution under a certain load is analyzed based on ANSYS, through which the maximum bending stress of the self-healing composite gears is obtained and the dangerous position is located. At the same time the same analysis is conducted on the composite material with no microcapsules. By comparing the analysis results of these two kinds of composite gears it shows that after adding 3.5wt% microcapsules the maximum bending stress of the composite gears decreased by 0.72% which can be seen basically unchanged, and their stress is almost in the same distribution with invariant dangerous position. The above result shows that the self-healing microcapsules have little influence on the static bending strength of composite gears.