Applied Mechanics and Materials Vols. 341-342

Abstract: A kind of force measurement mechanism which can measure the two-directional transient impact load in the same time is introduced in this paper, and the analysis research of the mechanical part are followed. First, by using the pro/E software, the 3D concrete model of the force mechanism is contributed. Then, by means of the ANSYS finite element analysis software, its stiffness and strength are analyzed, and strain and deformation figures from different directions are obtained. The static maximum deformation and strain of the force measurement mechanism and its key components, and also the whole distribution are showed in the analysis results. The weak parts of the force measurement mechanism and its key components are also showed in this paper, which can be helpful for the further improvement and following actual tests [.1]

Abstract: The problem of metal-composite wing structural optimization is discussed and a strategy is presented. Topology optimization method is applied to provide load transferring path of structure for concept design. Size, shape and other optimization method are used to provide detailed design for individual components. A three-phase optimization method is discussed for fiber reinforced composite laminate skin. Optimal parameters include ply angle, percentage, thickness, layer shape and sequence. The design of laminate for ease of manufacture is based on a set of manufacturing constraints. This paper deals with a total optimal design solution for aileron structure of an aircraft. The result satisfies all the requirements of strength and stability, and has obvious effect of weight loss.

Abstract: Numerical simulation is applied to study internal flow structure and performance of counterflow thrust vectoring nozzle with collar length in zero attack angle and subsonic conditions. The changes of thrust vectoring angle, resultant thrust ratio and secondary mass flow ratios are obtained. Results indicate that the thrust vectoring angle firstly increases and then decreases with increasing suction collar length, the max of which is 5.5o; but resultant thrust ratio decreases, and its range is 0.76-0.78;During the procedure of increasing suction collar length, suction flow shifts from counterflow to coflow, and mass flow ratio decreases.

Abstract: It brings certain error to reliability design of mechanical components that now most reliability design aiming at establishing pure theoretical mathematical model, without considering arbitrary distribution and variation rules of parameters. In this paper, the variation rules of strength and load effect are studied, the computational method of gradual change reliability is given. By combining the theory of reliability design with the method of sensitivity analysis, the restrictions on random variable distribution types are loosen, the gradual change reliability sensitivity design method with arbitrary distribution parameter is proposed based on the measurement information. Under the circumstance that knowing the first four order moments of basic random parameter, reliability sensitivity design with arbitrary distribution parameter can be brought about by using computer program, which provides the theoretical basis for structural design and life forecast of mechanical components.

Abstract: When the oilfield enters the hing water cut stage, the mining faces the problem that the oil-gas gathering system energy consumption reduction needs to decrease produced water and water injection. This paper proposes a novel multi-cup uniform flow gravity sedimentation single well injection-production technique. The downhole oil-water separator separates oil from water. The separated water is directly reinjected into the injection layer. Higher oil content of oil-water mixture is lifted up to the ground. The water injection and oil production in the production wellbore are simultaneous. This paper also designs a crown-like sedimentation cup structure. The experiment shows that the optimum structure of crown oil-water separator is cylindrical with 30 inclination, 12 edges and one partition baord on the tip at the bottom of corrugated shape. Produced liquid contains water 95 percent; efficiency can be increased more than three times by using multi-cup uniform flow gravity sedimentation separator.

Abstract: In order to obtain the flight stability of a flip-out tail fin shell of small length-diameter ratio and high aspect ratio, this paper calculates the supersonic viscous flow of the shell with the finite volume method, when the angle of attack exists. The six degree of freedom simulation is carried out with the previous results. The characteristics of the flow field around the shell ,static stability and dynamic stability are analyzed. The results show that lift coefficient can be described by linearity rule. Position of pressure center, which accounts for 10.3% of the total shell length, ranges from 0.3305 to 0.3945m. When initial disturbances are between 5and 9rad/s, maximum attack angle, which is apart from about 20m in the muzzle, is less than 5.5°. The amplitude of the angle of attack attenuates very fast and is close to 0° in 100m away.

Abstract: Based on the principle and method of computational fluid dynamics (CFD), using the software, FLUENT, the inner water flow field in the cross-section geometric model of a triangle-arranged tubular heat exchanger was simulated and the flow details were studied roundly. This article analyzed the temperature field distribution, pressure field distribution and pointed out the main factors that affected the effect of the heat transfer. The results of this paper provided a good base and reference for the further research on the optimum design.

Abstract: In order to realize simulation modeling of complex particle like corn, change the original rough and approximation methods, with the help of outer outline 3D scanning of the corn granule, scanning data are processed into the data that can be identified by Pro/ENGINEER, which are saved in the data base in this paper; through data mining, approximation simulation of ball filling is done to corn granule with cavity in the working environment of Pro/ENGINEER, which offers real, accurate and workable data for analysis and calculation of discrete element software behind the service.

Abstract: When the beam is transmitting, the random fluctuation motion of temperature and pressure of the medium inside the path of transmission will cause the random fluctuation of the index of refraction of the transmission medium. It will form wave front distortion when the beam is transmitting, which is known as the laser transmission turbulence effect. This effect mainly behaves as light intensity flashing, beam drift, phase fluctuation and beam expanding. Using FLUENT software simulate the status of turbulent gas in the environment with small space and large temperature difference (650°C). Verifying the laser transmission turbulence effect can be inhibited by artificial control the distribution of the gas flow inside the flow field, which can optimal the design of the instrument.

Abstract: In this paper, we obtain the detailed and precise data of the resistance performance in shallow water for the twin-skeg buoy tender in the different shallow-water conditions by the numerical stimulation of the resistance characteristic with the assistance of the commercial software FLUENT. Otherwise, the above obtained data are used to compare with the experimental results of the corresponding model in the towing resistance experiment. FLUENT is indeed competent and reliable for the calculation of the ship resistance.