Applied Mechanics and Materials Vols. 543-547

Abstract: The flow mechanism and radiate noise by a low-speed turbulent flow over an open cavity has been investigated computationally. After acquired the flow field data which is obtained by using Large Eddy Simulation, hybrid method that couples numerical flow computations with an implementation of the Ffowcs Williams-Hawkings equation is used to capture the flow induced noise. Different cavity length to depth ratios and configurations are used to investigate the influences of cavity deeps and configuration with an incoming flow of 50m/s. In this article, we also discussed the reduction method of cavity noise.

Abstract: For an air-to-air cooled medium motor, to ensure the cooling effect of the motor, the physical model of the motor cooling air inside the cooler was built. By the finite volume method according to the computational fluid mechanics (CFD) principle, the three-dimensional turbulent flow field in computational domain was simulated numerically using boundary conditions of the inlet and outlet obtained from engineering calculations. From the result, the thermal field of cooler was calculation. Finally, through the comparison, the cooler cooling the motor cooling effect sufficient play , the outer duct can effectively reduce the internal temperature of the cooling gas duct , the air duct outside the cooling gas declined about 35 °C after cooling the temperature of the air duct, the calculation method is feasible for the motor cooling system design overall foundation .

Abstract: The paper introduces the working principle of the pendulum rod bearing linear actuator and its kinetic characteristics. First, the model was built in SOLIDWORKS, then to do the simulation of ideal state and collision situations on this structure in ADAMS. At the same time, using MATLAB to get the ideal dynamic analysis results, including displacement, velocity and acceleration. The curves of input power and output power ware drawn out using ADAMS, then calculate the transmission efficiency of the mechanical mechanism. This research provides a theory and technical support for the application in all aspects of this mechanism.

Abstract: A method to predict the milling deformation of the cylinders deck face was carried out, and FEA technology was used in the research about machining deformation of the thin-walled part. In this work, a simple thin-walled part was taken as an example. The milling deflection of the workpiece had been predicted by establishing a FEA model. Finally, FEA results were verified with milling experimental data, which provided a theoretical basis for technology improvement of cylinders manufacture process.

Abstract: In view of the drawbacks of the traditional optimal methods in the suspension structure optimization, this paper elaborates a genetic algorithm (GA) based global optimal design so as to improve the vehicle performance. Firstly, an independent double wishbone air suspension (IDWAS) is constructed. After defining the linkage relation of the guide mechanism of the IDWAS, the model is verified followed with the parametric design. Furthermore, in consideration of the prescribed targets of the vehicle kinematics, the wheel alignment parameters (WAPs) are selected as the objectives of the optimal design of the vehicle kinematics. Apart from the kinematic analysis of the IDWAS, dynamic analysis before and after optimization as well as the traditional independent double wishbone suspension (TIDWS) are also conducted. Numerical results show that the changes of the WAPs are within a certain range and the guide mechanism follows the prescribed constraints. Simulation results show that the IDWAS is superior to the TIDWS, while the optimized IDWAS has a slight improvement as compared to the original IDWAS in dynamic performance of the suspension.

Abstract: In recent years, electric motion platforms are more popularly adopted in high-level driving simulators. This paper describes the kinematic and dynamics modeling for a high-level driving simulator. Firstly, the structure and kinematic models of the platform are introduced. Then, a linear engine simulation model in regard to the accelerator pedal is proposed. Tractive force and the resistance of the vehicle are also studied. Finally, a handling stability model with three degree of freedom is illustrated. All these models are used in the driving simulator of Chang'an University, which has a 6DOF electric motion platform.

Abstract: A concept, coupling screening, has been put forward and the method of the coupling screening is proposed based on the analysis of solo particle kinematics on flat vibrating screening and rotary screening. The kinematics model of coupling screening about solo particle has been constructed. The structure design of coupling screening machine has been done too. Eventually, with analysis of influence factors on relative geometric feature of material is carried out.

Abstract: Automated strap-down vertical drilling system (AVDS) with independent intellectual property rights is composed of a strap-down stabilization platform and a deviation control and correction mechanism. It performs deviation control and correction initiatively while drilling by applying dynamic push-lean, which can effectively solve the inclination control and fast drilling problems arising from high-steep structures and high dip formations. The system can release drilling pressure completely, so under the precondition of ensuring inclination precision, it could remarkably improve the penetration rate, shorten the drilling cycle and reduce the drilling costs. During the field test from 2436 to 2610.79m in well Anshun-1, inclination angle decreased to 0.25° from 6.25°. The average ROP was 1.02m/h, and the average footage was 87.4m. Compared with traditional drilling tools, it improved the penetration rate by 25.9% and the footage by 18.3%. The stability and reliability of the system was proved through the field test. It was suggested that field tests should be strengthened and AVDS applying for different borehole should be developed.

Abstract: Numerical simulation technology not only could effectively predict the defects on the forming product, such as wrinkle , rupturing, but also could display the stress, strain distribution and forming pressure. The numerical simulation was completed by DYNAFORM solfware, and the result of numerical was using to conduct the double-wall air compressor forming parts forming process inspection and forming mold design optimization.

Abstract: Multi-Block OFDM (MB-OFDM) structure has been proposed recently for fiber-wireless networks. MB-OFDM transmission scheme can simultaneously solve some problems of conventional OFDM, such as high peak-to-average power ratio (PAPR), and severe sensitivity to carrier frequency offset (CFO). However, in the transmission scheme, one guard interval shared by multiple blocks, is not suitable for fast fading channel in vehicular environment. In this paper, we propose a novel MB-OFDM structure and use the frame to transmit data in vehicle-to-vehicle (V2V) communication scenario. From computer simulation, it is confirmed that proposed structure can provide better ICI cancellation performance than conventional OFDM.