Advanced Materials Research Vols. 594-597

Abstract: A theoretical analyzing approach about the compound floor isolation system consisting of RFPS and dish spring is derived. Computation results show that for the proper specifications, the floor isolation system may exhibit good effectiveness in mitigating the acceleration of the unfixed objects or equipments in both horizontal and vertical direction, while the extra displacement could be limited to be in a manageable range. The expected parameters for mitigating the accelerations agree with that for displacements in a partial domain. The specification of a floor isolation system needs low friction coefficient on the slide 0.05<μ<0.1, a reasonable slide radius 0.6<μ<1.0m, a relatively low stiffness coefficient and relatively high damp coefficient of the dish spring.

Abstract: According to the actual structure of steel wire wound reinforced rubber flexible pipe, using the finite element software ANSYS, 3-D finite element model of flexible pipe is established. For the mechanical response of flexible pipe under internal pressure, the comparison on the result by numerical calculation, the static loading test and the result by analytic method shows that the 3-D finite element model of flexible pipe is rational. Moreover, based on the finite element model of flexible pipe, the influence of internal pressure, spanning length and reinforced steel wire diameter on the axial stress of the innerest steel layer and the Mises stress of the innerest rubber layer is analyzed.

Abstract: In the paper basic knowledge of thorn pile and the working principle characteristics are introduced in different directions. Mechanical equilibrium conditions of thorn pile are that Adjacent to the piston must be each other angle of 60 °and Hydraulic cylinders are assembled In the longitudinal. The paper laid the foundation for the design and use of thorn pile extrusion forming machine.

Abstract: Although the conventional Reynolds-averaged Navier–Stokes (RANS) model has been widely applied in the industrial and engineering field, it is worthwhile to study whether these models are suitable to investigate the flow filed varying with the time. With the development of turbulence models, the unsteady Reynolds-averaged Navier–Stokes (URANS) model, detached eddy simulation (DES) and large eddy simulation (LES) compensate the disadvantage of RANS model. This paper mainly presents the theory of standard LES model, LES dynamic model and wall-adapting local eddy-viscosity (WALE) LES model. And the square cylinder is selected as the research target to study the flow characteristics around it at Reynolds number 13,000. The influence of different LES models on the flow field around the square cylinder is compared.

Abstract: Underwater explosion is very important for underwater weapons-design technology and research on the damage effect of target structure. In this paper, the flow-out boundary and variable step-size multi-material Euler algorithm were utilized to analyze numerically the whole process of shock wave generation and propagation, as well as bubble formation and impulse of underwater explosion. The computed results reveal the energy output characteristics of underwater explosion by TNT charge, which provide an important scientific basis for formulation design of charge and improvement of damage effects for underwater target.

Abstract: In order to analyze the characteristics of the liquid flow in hydrophilic micro-channels, the negative slippage in the hydrophilic micro-channels were studied by molecular dynamics simulation and experimental research in this paper. The simulation results indicate that there exists negative slippage in the small shear rate. The absolute value of slip length decreases with the augment of shear rate and keeps constant when the shear rate increases to a certain extent. In the condition of same wettability, the slip length is only relative to shear rate of fluids near the wall rather than channel widths. At last, a experiment of deionized water flow in the micro-channel of 10 diameter was carried out. The experimental results have a good agreement with the simulation, and there exists Pseudo Threshold Pressure Gradient(PTPG) under low flow velocity. The negative slippage as the reason of existence of PTPG is analyzed in low permeability porous media

Abstract: Ship collision is a kind of dangerous accident which may result in serious damage of struck hull structure during shipping process. The damage of ship depends on the relative rigidity of striking ship and the capabilities of crash resistance of ship structures. The rigidity of bow is always considered as higher than that of side, so the structure of bow is regarded as rigid body. But this method is so conservative that the result of numerical simulation may be wrong when the rigidity of side of one ship is higher than that of bow of another ship. The process of collision of two ships is simulated, in which the structures of two ships are all defined as elastic body. The behavior of side is studied and some useful results are found.

Abstract: In this paper, a Lotka-Volterra model with time delay is considered. The stability of the equilibrium of the model is investigated and the existence of Hopf bifurcation is proved. Numerical simulations are performed to justify the theoretical results. Finally, main conclusions are included.

Abstract: Based on the experimental materials, bond–slip behavior of the steel reinforced concrete (SRC) column is studied here. According to the characteristic of the loads, the slip displacements formulation between steel and concrete of a SRC column subjected to push-out load is derived by energy method. The calculation results show that the slip curves have the basic characteristic of quadratic curves distribute.

Abstract: Removed at authors request.