Applied Mechanics and Materials Vols. 541-542

Abstract: This present research work is focused on obtaining the combination of the optimal levels of the parameters notch angle, heat treatment processes & height of the hammer in order to maximize the impact value of mild steel, having 0.40 % carbon, in an izod impact test. The process evinces hammering effect on the specimen that ascertains the amount of mechanical energy required for the failure of any material. This research work investigates the effect of all the three parameters on impact values. The optimal values of the parameters were determined using design of experiment (DOE) via taguchi method with the application of used Orthogonal Array. Signal-to-noise ratio and the analysis of variance were used for the further analysis. The important findings of the experiments show that height of the hammer was the only parameter that affected the impact values significantly. The findings were followed by affirmations by performing the confirmation experiments.

Abstract: A multi-objective structure optimization design onthe upper carriage of a naval gun was operated in order to improve both compliance and eigenfrequencies effectively. Based on SIMP (solid isotropic material penalization) method, compromise programming method was adopted to define multi-objective topology optimization. The topological structure of upper carriage was obtained through the optimization, and further, the new structure design. Results verified by FEA show that the new design can simultaneously satisfy the compliance and eigenfrequencies objective, and meanwhile candecrease mass and stress.

Abstract: The liquid cargo movement within a partly-filled tank truck affects its braking, roll dynamics and directional performance in an adverse manner. In this study, the braking performance of a partly-filled tank truck equipped with different baffles designs is investigated considering dynamic fluid-structure interactions. The validity of the computational fluid dynamic model is examined through laboratory tests conducted on a scale model tank with and without baffles. The measured responses to harmonic excitations revealed three-dimensional nature of the fluid motion and couplings between the lateral and longitudinal fluid slosh. Several spectral components were observed for the transient slosh forces, which could be associated with the excitation, resonance, and beat frequencies. A dynamic pitch plane model of a Tridem truck incorporating three-dimensional fluid slosh dynamics is subsequently developed to analyze the fluid-vehicle interactions under straight-line braking maneuvers. The results show that the vehicle responses are highly influenced by the slosh-induced force and moment.

Abstract: In order to make the virtual experiment results close to or equivalent to the real movement patterns, the agricultural machinery virtual test based on virtual reality requires realistic scene model and it also needs more accurate agricultural machinery dynamic model.As for the rice and wheat combine harvester of hydraulic steering, firstly, model transformation technology is used to convert Pro/E harvester model into three-dimensional geometric model that can be identified by Vega Prime virtual reality systems. Secondly, classical dynamics equation is used to construct the mathematical models of the rice and wheat combine harvester. Finally, mathematical models are combined with geometric models by VC++ programming, and then the physical behavioral model of combine harvester which has the physics properties is created.It can effectively strengthens the authenticity of agricultural machinery virtual test, and provides an important platform to start agricultural machinery virtual characteristics test. The modeling method can provide an important agricultural machinery dynamic model for the further virtual test based on virtual reality.

Abstract: During hypersonic flight or cruise in the near space, the aerodynamic heating causes a very high temperature on the leading edge of hypersonic vehicles. Transpiration cooling has been recognized the most effective cooling technology. This paper presents an experimental investigation on transpiration cooling using liquid water as coolant for a nose cone model of hypersonic vehicles. The nose cone model consists of sintered porous material. The experiments were carried out in the Supersonic Jet Arc-heated Facility (SJAF) of China Academy of Aerospace Aerodynamics (CAAA) in Beijing. The cooling effect in the different regions of the model was analyzed, and the shock wave was exhibited. The pressure variations of the coolant injection system were continuously recorded. The aim of this work is to provide a relatively useful reference for the designers of coolant driving system in practical hypersonic vehicles.

Abstract: Motorcycle fender is one of the main components of motorcycle,fender structure directly affected it's comfort and security properties.In this paper, the finite element modeling and dynamic response were analyzed using NX 8.0, and found its natural frequencies and mode shapes. On the basis of the fender structure modeling on different road with the same speed, this paper investigated the several factors affect the vibration motorcycle and analyzed true fender of the motorcycle and did comparative analysis with the modal analysis results. It is helpful to the design of the fender structure and the estimation of the fender fracture. Key Words: Fender;finite element method;modal;Dynamic response

Abstract: On the research and development of the Stack-Manipulator to Aluminum-Ingot, the Stack-Manipulator 3D model was established by using SolidWorks and imported into ADAMS via the interface between them. And then the authors got the torque and angular velocity curves after adding the driving and constraints. Finally, this paper chose the servo motors by using the simulated results. The results provide a reliable and scientific basis for the development of the control system.

Abstract: The authors build the three-dimensional model of stack-manipulator to aluminum-ingot in SoildWorks,and then import the model into Adams to create a simulation model via the interface between them.Adams runs dynamic and kinematics simulation of the model to measure some kinematic data of manipulator and the contact force of gear part.The dynamic simulations have forecasted the performance of products based on the model well and show the importance of Adams in product development.

Abstract: In the process of wire electrical discharge machining, the wire electrode inevitably suffers bending deformation due to wire tension, electrostatic force, electrodynamics force, etc., and the deflection would make an clearly negative impact upon the machining accuracy, productivity and stability. In this paper, first of all, a novel modeling and simulation method is proposed for quantitatively calculating the wire deflection. Secondly, the mainly impact factors and trend of wire deflection have been concluded. Moreover, the feasibility of the model is proved by comparing with other researchers models. Eventually, the practical approaches of reducing wire deflection and improving the machining accuracy have been proposed.

Abstract: In the same well water flooding process, solid particles contained in the fluid often result in the impeller submersible electric pump to erosion wear. We use Fluent software to establish the model of flow field,and use numerical simulation method to analyze the erosion wear. We use the erosion theory to calculate the erosion wear rate,and verify the correctness by the contrast between the results of numerical simulation and actual value.