Abstract: In order to research the external spur-gear pump shell, use of ANSYS software to make strength analysis, through the simulation to get displacement deformation clouds and equivalent stress clouds,and find shell the maximum displacement deformation position and the maximum stress position.The optimization results show that in the shell security meet conditions, its quality was reduced by 5.9%, the stiffness of the shell has been improved greatly.At the same time,noise of the pump has been reduced, extending the service life of the pump. The study conclusion for improving the gear pump structure design and perfecting its mechanical performance provides theory basis.
Abstract: New direct method was developed for fibre reinforced polymers subjected to fatigue loading. Constitutive model is based-on coupled plasticity-damage framework. Microstructure of material is satisfying the periodic conditions. Influence of microstructure has been involved through stress concentration tensor. Plasticity yield surface is described by modified Raghava criterion. Damage of matrix and transverse cracking are governed by quadratic damage surface. Method was examined on the standard example of unidirectional composite plate with carbon-fibre reinforced. Significant reduction of calculation time has been achieved using the direct computational algorithm.
Abstract: The paper deals with numerical simulation of Small Punch Test (SPT). SPT is a penetration test used to determine basic mechanical properties from a tiny piece of material. The testing procedure drew a great interest in the last decade, nevertheless there are no generally accepted standards for this type of testing until now. “Code of Practice” was created as a consequence of the CEN Workshop 2007, recommending both geometry, experiment performance and its basic evaluation. To obtain other mechanical properties like flow curve, yield stress, ductility and ultimate strength, it is necessary to realize a numerical simulation of the test to identify the mentioned material parameters. As the SPT results are generally influenced by many other parameters besides material behaviour, we try to quantify their relevance to make the material identification more rigorous.
Abstract: The droplet breakup is of importance in variety of spay combustion field. In order to investigate gel propellant droplet breakup in a gaseous phase, the Navier-Stokes equations in their axi-symmetric form was solved using the finite volume technique, and the Volume of Fluid method (VOF) was employed for tracking the free liquid-gas interface during process of droplet breakup. The results were compared with available published experimental data for Newtonian droplet, and validated the numerical model. The results show that increasing Weber number (We) can accelerate drop breakup; under the low shear rate, increasing K leads to droplet more resistant to breakup, drop breakup is dominated by K value; under the high shear rate, reducing n value results in stronger the shear-thinning behavior, and a decrease in resistant to breakup, n value governs the droplet breakup.
Abstract: Introduce structure and working principle of shock excitation hydraulic system in VSR equipments, establish its simulation model with advanced modeling software .Through dynamic simulation get simulation curves under different conditions, and analyses some important parameters’ influents on the system, and provide the basis for testing and improving the system.
Abstract: In the light of the problems that mine air compressor’s exhaust pressure instability, large energy consumption in the work process, more waste and so on, the system used PLC as the developing platform of the hardware, using fuzzy PID parameters self-tuning method to control the air compressors, make it possibly that air compressors’ main motor variable frequency speed regulation, ensure air compressors supply air stability, using Matlab/Simulink software to model and simulate and analysis for the control system at the same time, through the field test and the simulation results show that, this system not only improved the automation degree of the air compressors’ system, but also the obviously voltage stabilizing and energy saving effect, it has a greatly applied prospect and practical value.
Abstract: This paper presents a solution to helicopter maneuver flight simulation according to ADS33 flying qualities requirement standard. Associated with aerodynamics and control law design methodology, the proposed scheme achieved satisfactory control performance by analyzing helicopter attitude and control parameter variation law at certain operating condition. To level flight acceleration, method based on force and moment balance is analyzed. To pirouette maneuver, a segment linear approximated trajectory is developed for attitude and velocity stability. All objective function is based on minimizing position error and attitude error. For a single rotor four bladed model helicopter in pirouette maneuver, experimental results certified its efficiency.
Abstract: Based on the theoretical analysis on working principle and motion of the electro-hydraulic proportional variable piston pump, it created and simulated the model in the AMESIM software. The influences of main structural parameters of variable pump on system output dynamic characteristics were revealed after simulating analysis results of pressure control characteristics. And the steady state output of system pressure is proportional to the input voltage of amplifier. The overshoot decreases with the increasing of input voltage, and the response get faster. The damping aperture of proportional reversing valve and core diameter of control plunger have a greater influence on the dynamic response of system.
Abstract: In this paper a dynamic simulation methodology of systems is presented by using ADAMS/MATLAB co-simulation. This methodology allows simulation, development and validation of different control strategiesfor robotic manipulator models in a fast way. It provides a first stage into the design of robotic prototypes for researchers and professionals. Finally, the methodology was validated by constructing a simulation model of a double pendulum and by implementing a PD type control strategy.
Abstract: Ant colony algorithms are computational methods inspired from the behavior of real ant colonies. In this paper our interest is focused on the adaptation of an optimization algorithm called API based on the foraging behavior model of primitive ants’ population called Pachycondyla apicalis to solve real time alternative routings selection problem in a Flexible Manufacturing System (FMS) with and without presence of breakdowns. The FMS consists of seven machining centers, a loading and an unloading stations, and six different part types. Owing to the presence of identical machining centers, the parts have alternative routings. The scheduling decisions has been established in terms of how the parts are routed through various machines in the system.