Applied Mechanics and Materials Vol. 404

Abstract: Longitudinal liquid sloshing in partially-filled tankers has great influence on vehicle braking performance, which results in serious tanker crash accidents. To investigate the influence of shape and location of holes that pierced on the baffle on reducing liquid sloshing and on the force analysis of baffles. Three different shapes of holes are designed and each hole has two assemble position on the baffle. FLUENT is used to simulate liquid sloshing in partially - filled tanks that equipped with different kinds of baffles which subjected to constant braking deceleration. Time-series analysis of forces on tank walls and baffles are carried out considering structural damage both the tank head and the baffles. It is drawn that the shape of manhole has great influence on baffle anti-sloshing effect and the position of manhole has giant impact on baffle force analysis.

Abstract: This paper presented a new dynamic optimal design method of wind turbine blade which combined the Wilson model with the BEM aerodynamic model. Considering the wind energy utilization coefficient as the target function, the Wilson theory was used to optimize a 1.5MW blades aerodynamic shape. The revised distribution of chord and twist angle was nearly of linear change in the main output power section of blade. The optimized wind energy utilization coefficient can reach 0.552, which is very closed to the Betz limitation. In the part of the calculation of aerodynamic performance, considering both the effect of solidity and eddy current loss on the aerodynamic performance calculation, and also considering the sensitivity of the initial value in a nonlinear equation, it utilized the blade element momentum theory (BEM) which was a classical method on the aerodynamic performance of blade to calculate the aerodynamic performance.The results shows the optimized power output can be up to 1.3426MW, and compared with the rated power, the efficiency reached 89%.

Abstract: The paper discussed the working principle of the hydraulic brake system, and built a model in the simulation by using AMESim to analyze performance of this system. The paper also established a test bench of hydraulic brake system, and the test result coincided with the consequence of simulation, thus to prove the simulation model and method reasonable. This simulation can shorten design cycle of hydraulic brake system apparently, and it contributes a good method to assistant brake system design.

Abstract: A numerical investigation has been conducted to research the interaction flowfield of lateral jet not in the longitudinal symmetry plane on a slender body with rudders in supersonic flow. The surface and space flow features of jet interaction flowfield with different angles of attack was analyzed. The paper also compared with and without jet interaction flowfield characteristics. As a result, the jet interaction destroys pressure distributions of the slender body, and causes normal and lateral loads. With angle of attack, the pressure distributions of the after body and rudders surfaces are change tempestuously. The results also show that the far-field interference played a major role in the lateral jet interaction. Besides, the force/moment amplification factors present highly nonlinear with angle of attack.

Abstract: This paper discussed the pressure drop about the friction pressure drop and gravity pressure drop in the pipe. Represent the model of pressure drop. Calculate the pressure drop in the experiment system. Flow pattern and pressure drop has the directly relationship. And the friction pressure drop is the main factor of influences internal fluid mechanism. Pressure drop is basic of research the water rate and dynamics fluid.

Abstract: In this paper, the gear shaping of some planetary gear was simulated. The simulation results show that via the gear shaping process, the gear tooth surface on the left has a single tooth pitch deviation of about 1.2 um, and the gear tooth surface on the right has a pitch deviation of 1.1 um, accordingly. By combining the simulation of two-dimensional and three-dimensional gear shaping models, this paper can not only realize accurately the gear shaping process of the planetary gear, but also provide some certain reference for the gear shaping processing.

Abstract: A dynamic model for helical planetary gear train (HPGT) is proposed. Based on the model, the free vibration characteristics, steady-state dynamic responses and effects of design parameters on system dynamics are investigated through numerical simulations. The free vibration of the HGPT is classified into 3 categories. The classified vibration modes are demonstrated as axial translational and torsional mode (AT mode), radial translational and rotational mode (RR mode) and planet mode (P mode) followed by the characteristics of each category. The simulation results agree well with those of previous discrete model when neglecting the component flexibilities, which validates the correctness of the present dynamic model. The steady-state dynamic responses indicate that the dynamic meshing forces fluctuate about the average static values and the time-varying meshing stiffness is one of the major excitations of the system. The parametric sensitivity analysis shows that the impact of the central component bearing stiffness on the dynamic characteristic of the HPGT system is significant.

Abstract: This paper uses a mathematical model Virtual Identity Particles, developed by the author, to simulate conjugated motion of complex particles in a fluid. Assimilated the advantages of Eulerian and Lagrangian approaches, this model treats each particle as a variable source term to the fluid and is designed for simulating numerous particles in two-phase flows. The economic formulation in this model is the salient feature. Considering both precision and computational cost, this model maintains an excellent balance between accuracy and efficiency in modeling particulate flows with complex particles. Simulation results demonstrate that this model is viable for investigating complex particulate flows, especially at a moderately high particle number density.

Abstract: The primary characteristics of Modelica language is described, The steady and dynamic mathematic model of aircraft engine are introduced. The methods of the main components in the aircraft engine generic model library developed by Modelica/Dymola software are expounded. The system level model of a two-spool turbofan engine is built and its steady and off design state is simulated. The results accord with the actual situations, so that the library can help in constituting the simulation system of variety engine with great importance and practical value in conceptual and preliminary design.

Abstract: Establish a CFD simulation interface for compressor aerodynamic analysis based on general CFD software. The simulation interface includes data format, process and interface standard. Data format based on CGNS is built for cross-platform restoring and retrieving mass data. The designing of process references the process of general CFD analysis and the compressor aerodynamic analysis. The interface standard is used to import and the parameters and export them into corresponding profiles according to the demand of different computation modules. Validation results for the simulation interface using a single-stage transonic axial compressor fan ATS-2 shows that the setting process is more convenient and achieves a certain degree of automation.