Advanced Materials Research Vol. 662

Abstract: The generation method of traveling wave and the driving force source in straight micro channel were investigated based on the vibration theory. The analysis shows that the driving force in traveling wave micro-pump is closely related to the fluctuations of the channel wall and there is traveling standing wave along the straight micro channel. Through fluid-structure coupling analysis, flow characteristics in straight micro channel are obtained as well as the outlet velocity. The average outlet velocity is about several hundreds of nanometers percent second if only the mechanical force is considered. The influence of the driving voltage on the velocity is also analyzed to provide guidance on the optimal design of the traveling wave micro-pump.

Abstract: Embarking on the need of agriculture yield estimation and yield capacity, and the need of wheat threshing in agricultural colleges and research institutes, this text gives the design of miniature Direct-Current (DC) electric threshing machine using storage battery as power source based on the characteristics of the DC which is easy for storage. At the same time , the threshing machine is driven by a DC motor, considering the field threshing of the yield capacity and the yield estimation and the reality needs of small sample nicety threshing. The device has the advantages of light weight, small volume, simple operation, easy maintenance, convenient carrying.

Abstract: Droplet streaming and nebulization on a shear horizontal surface acoustic wave device made of 36o Y-cut LiTaO3 have been reported. The streaming pattern inside the droplet is sensitive to the droplet shape, the position to the interdigital transducer, and the aperture size. Droplet nebulization was enhanced with the increased aperture size of the driven IDTs and mainly occurred in horizontal direction along two lateral sides of the droplet, which is perpendicular to the designed SAW propagation direction. The atomization duration increases with the droplet size and decreases with the driven power at a given droplet size. The maximum rate of the atomization is ~0.2 μL/s at an applied power of 6.7 W. This provides a simple and effective method of the integration of both bio-liquid sensing and fluid manipulation on a single substrate for lab-on-chip biosensing platform.

Abstract: Four types of Super Typhoon drip emitter with trapezoidal channel were selected out for the investigation of the flow field of the channel, and the CFD (Computational Fluid Dynamics) method was applied to simulate the micro-field inside the channel. The simulation results showed that the emitter discharge of different turbulent model is 4%-14% bigger than that of the experimental results, the average discharge deviation of κ-ω and RSM model is 5, 4.5 respectively, but the solving efficiency of the κ-ω model is obviously higher than that of the RSM model.

Abstract: A simplified rigid-flexible coupling dynamical model of the rail operating vehicle, including bogie frame and car body, was built. The car body is modeled as a flexible uniform Euler beam. The dynamical response of the vehicle under the irregularity dynamic action between wheel and rail was numerically calculated and analyzed by the fast stability algorithms. Influences of the suspension on vibration and stability of the vehicle are analyzed. The results have a certain reference value on the dynamic design of multi-functional track operating vehicle.

Abstract: In order to get a profound understanding of planet motion and orbital motion in CCOS (Computer Controlled Optical Surfacing), a compare study between them was conducted here. The material removals of two motions under the same conditions were simulated and the removal of planet motion was higher than that of orbital motion. The figuring abilities of two motions were also studied through the theory of cut-off frequency and the result showed that planet motion had a higher cut-off frequency. Then two figuring runs which employ the planet motion and the orbital motion were simulated. The convergence rates and polishing times of these two runs were compared and the result showed that planet motion had a higher figuring efficiency. As planet motion has stronger figuring ability and higher figuring efficiency, it’s better to employ planet motion in CCOS to get higher convergence rate and higher accuracy when fabricating high quality mirrors.

Abstract: The flow process of tangential vane burner of pressure oil-burned boiler was numerically simulated with realizable k-ε model. Burner flow field boundary, air axial velocity and air tangential velocity were measured. The measure was done under cool condition, at 28% load and 0.1MPa, the simulation was done under the same conditions. The calculation had a good agreement with the experiment. Flow field was calculated under cool condition, when pressure was respective 0.1MPa, 0.2MPa, 0.3MPa, 0.4MPa. Recirculation zone length and maximum diameter both decreases with pressure increase. Axial velocity decreases with pressure increase. Flow field was calculated under heat condition, recirculation zone length of heat condition is 2.67 times longer than under cool condition; recirculation zone maximum diameter is 2.53 times longer than under cool condition; recirculation zone position is ahead 200mm than under cool condition.

Abstract: In this paper, to research the independent suspension system of three-axle vehicle ride comfort, developed a nine freedom model of vehicle dynamic. Utilized Lagrange method to derive the system vibration equation, absolute value of the center of mass acceleration metrics, computer simulation in time domain of the vehicle ride on D grade road that use the SIMULINK was carried out, analysis verify the correctness of model. To analyze the vehicle ride comfort by changing the distance between the triaxial in model, improve vehicle ride optimize reference.

Abstract: Aiming at a rotor model, the coupled bending-axial vibration is being analyzed.Calculation results show that the prestress relative to rotational centrifugal load may influence bending vibration frequencies of a rotor.The bending vibration frequencies will increase when the prestress increases.The axial vibration frequency has not an influence because the direction of the spinning prestress is perpendicular to axis.When a rotor is applies axial force, a compressional force will tend to increase the axial vibration frequencies while a tensile force will decrease the axial vibration frequencies.The effects of the prestress(centrifugal load )of the spinning rotor and the axial prestress can be accounted by an adjustment of the stiffness matrix for analysis.By use of the stiffness matrix,the changed axial and bending vibration frequencies can be explained.The coupled bending-axial vibration may take place when the bending vibration frequencies have increased in the state of the changed prestress.In the end, the coupled bending-axial vibration frequency can be calculated.On the basis of prestress, the coupled lateral-torsional vibration and the coupled torsional-axial vibration frequency can be analysed,similarly.

Abstract: In order to achieve the goals of small aircraft’s taking off and landing in any posture and the protection of propeller, a new single-propeller spherical aircraft structure was proposed, which had the capacity of flying in the air and walking on the ground simultaneously. An aerodynamic model of the aircraft was built. The aerodynamic characteristics of the spherical aircraft, including the lift and the anti-torque and the generated torque of the flow deflectors under the propeller’s down airflow, are studied in depth by means of CFD numerical simulation method. A reasonable design and installation program is proposed according to the research results.