Applied Mechanics and Materials Vols. 217-219

Abstract: Numerical models have been developed to study the characteristics of an arc inside the non-transferred plasma torch. A few of them have considered the diameter of anode spot and arc length in given current and gas flow rate. In this work, a three-dimensional model is developed to simulate power and entropy in the given current and diameter of anode spot. Different combinations of diameter of anode spot and arc length can produce torch power that corresponds to given current and gas flow rate. From the possible combinations of the diameter of anode spot and arc length predicted for given current and gas flow rate, the most feasible combination is obtained.

Abstract: The purpose of the present paper is to investigate the influence of charge shape on the air blast loading near the explosive. By using MSC. DYTRAN, the air blast loading of spherical charge, cubical charge and cylindrical charge with the same weight were simulated. After the characters of shock wave, peak pressure and impulse of such three charges were compared, it can be seen that there are different decay law for peak pressure of cylindrical charge, cubical charge, spherical and experiment formula. There are also different magnitude relation for the impulse at different scaling distance.

Abstract: Cushion has a wide range of applications in engineering. It is a new attempt to use it in the field of printing and packaging lamination process, to get a numerical simulation study analyzes for the distribution of the formation pressure of the air cushion pressure chamber. On the basis of analysis of the principle of air-cushion laminated device, make it clear for the requirements of the air cushion pressure distribution, pressure distribution from a single stomatal mathematical model, using ANSYS finite element software, numerical simulation of multi-stoma pressure distribution. The results showed that: stomata arranged in the form of cushion thickness, stomatal spacing and stomatal row spacing uniformity of the distribution greater impact on the cushion pressure; small stomatal spacing and stomatal row spacing will help improve the air cushion pressure distribution uniformity; reasonable cushion thickness stomatal spacing and stomatal row spacing, the selected diameter of the pores smaller cushion pressure distribution uniformity.

Abstract: A refined theory of axisymmetric cylinder in one-dimensional (1D) hexagonal quasicrystals (QCs) is analyzed. Based on elastic theory with 1D hexagonal QCs, the refined theory of axisymmetric cylinder is derived by using general solution of 1D hexagonal QCs and Lur’e method without ad hoc assumptions. At first, expressions were obtained for all the phonon and phason displacements and stress components in term of the three functions with single independent variable. Based on the boundary conditions, the refined equation for the cylinder is derived directly. And the approximate equation is accurate up to the second-order terms with respect to radius of circular cylinder.

Abstract: A numerical analysis was performed to investigate the temperature distribution and thermal stress field in monocrystal silicon rod in the cooling process of manufactured with Czochralski (CZ) method. The thermally-induced residual stress fields of silicon rod under different length of cool-down time conditions were obtained as well as temperature fields, respectively. All simulations were finished by using ANSYS finite element code. It showed that, maximum thermal stress was mainly appeared on rod surface, the influence of length of cool-down time on it was not remarkable, the magnitude of it was far below the critical strength of silicon throughout.

Abstract: A conceptual design of a drop-on-demand(DOD) micro metal droplet print head, which is characterized as the non-heat affection of piezoelectric actuator and a desirable controllability on droplet condition, is devised. With a 2D axisymmetric model and a VOF model, the droplet evolution is simulated for understanding the mechanism within. Parametric studies are followed to investigate relationship between droplet condition and print head parameters for realizing accurate control of droplet condition.

Abstract: The paper aims at the simulation on double tank water level control based on MATLAB .Double tank water level control belongs to large time delay system. In this paper, adopted PID method to control the system, Then, fuzzy PID control method was used to adjust this second-order system. And the simulation model of this system is built with MATLAB Fuzzy and SIMULINK. And at the end, analysis the system stability ,reaction velocity and so on.

Abstract: Twin-roll casting is an efficient and economical process to fabricate metal sheets since it combines solidification and rolling in one process. However, this process requires a careful control because several phenomena, such as heat transfer, solidification, fluid flow and solid deformation, occur simultaneously. In the present study, a rigid-thermo-viscoplastic finite-element analysis was utilized to understand these complex phenomena occurring in a vertical twin-roll casting of an aluminum alloy. As a result several interesting findings were obtained including the development of two symmetrically identical vortexes at the roll entrance.

Abstract: The job-shop scheduling problem (JSP), which is one of the best-known machine scheduling problems, is among the hardest combinatorial optimization problems. In this paper, the key technology of building simulation model in Plant Simulation is researched and also the build-in genetic algorithm of optimizing module is used to optimize job-shop scheduling, which can assure the scientific decision. At last, an example is used to illustrate the optimization process of the Job-Shop scheduling problem with Plant Simulation genetic algorithm modules.

Abstract: The process of the supercavitation projectile penetrating into metal targets was simulated by using the dynamic analysis software ANSYS/LS-DYNA, and the deformation、breakage and forces on the body in different initial velocities and the penetration depth were discussed. Analysis results show that there are two peaks of resistance and the velocities is variety almost in linear attenuation when the cone part of the projectile is moving through contacted with the target plate, which provides references for the structure and parameters design of the supercavitation projectile.