Advanced Materials Research Vol. 744

Abstract: Performances of vanes with various numbers and front oriented-body with different shapes such as half sphere, half ellipsoid and cone are simulated by RNG κ-ε model and standard wall functions method in order to optimize the parameters of the front oriented-body attached on the new bidirectional flowmeter. The performances of weakening-vortex and the pressure losses attaching to various models are analyzed and compared with each other. The results show that the structure with cone guide-head and 6 vanes can obtain the minimum range of flow pulsation, the least pressure loss and the least reverse flow. The simulation methods and results will be used for reference to analyze the similar annular flow and design the steady device.

Abstract: A new biaxial decoupled resonant micro-accelerometer is researched. The new biaxial resonant micro-accelerometer consists of four same tuning forking resonators, four pair of decoupled beams, four lever mechanisms and a proof mass. The decoupling between two orthogonal axes is realized by the decoupling beams, which will benefit to isolate two axes acceleration detection. The simulation is implemented to verify the basic principle by the Ansys. The simulation results prove that the effective frequencies of two acceleration sensitive modes are 3.699 kHz and 3.718 kHz separately. Two pair of resonator modes which are 23.893 kHz, 23.946 kHz, 26.974 kHz and 26.999 kHz separately have about 3kHz difference in frequency in order to prevent the mutual interference. And the interference modes are isolated with effective mode apparently. The input-output characteristic simulation results indicate the y-axis scale factor is 57.1Hz/g and the coupling output in the x-axis is 0.0148Hz/g, while the x-axis scale factor is 56.1Hz/g and the coupling output in the y-axis is 0.0073Hz/g, which proves that the new biaxial resonant micro-accelerometer is practicable and has an excellent decoupled performance.

Abstract: Due to working in natural environment in a long term and dust deposited on the surface, air cooling radiator turns to a lower heat transfer rate, so that it leads to load limit operation for air cooling unit in summer. In allusion to indirect air cooling radiator with Heller System, high-pressure water jet technique is used and built-in cleaning device is designed to entirely solve above-mentioned problem. Cleaning device works automatically and realizes full cover cleaning. Cleaning-pressure is between 100 and 150bar and cleaning target distance keeps within 200mm. Dust on the surface of radiator can be entirely cleaned. Cleaning flow is 20m³ /h and the cleaning cost decreases greatly. Such device has been successfully tested and worked. Furthermore, it has been applied to the project with a system of 2×600MW supercritical indirect air cooling unit.

Abstract: Thermo luminescence dosimeter and optically stimulated luminescence dosimeter are the most popular dosimeters for personal and environmental radiation monitoring. Basically, these dosimeters are both accumulated dosimeters so that they cannot precisely measure dynamic doses, i.e. there is no any information of time resolving. We developed an algorithm to solve the problem that can depress the uncertain measurement by using partially bleaching techniques; the two-stage bleaching method under the fixed bleaching intensity condition. To analyze and compare the difference of ionizing radiation dose between two dosimeters can partially recall the non-uniformly distributed radiation doses. The Gaussian distribution of dose is considered for the simulation and the results indicated that error of the dose rate could be depressed to 15% compared to the traditional method.

Abstract: Resonant micro-accelerometers have good properties such as the large dynamic range, the high sensitivity, the strong anti-interference ability as well as the direct digital output. A new z-axis resonant micro-accelerometer based on electrostatic stiffness is researched. The new z-axis resonant micro-accelerometer consists of a torsional accelerometer and two plane resonators. The sensing movement of the accelerometer is decoupled with oscillation of the plane resonators by electrostatic stiffness, which will benefit to improve the performance of the new z-axis resonant micro-accelerometer. The new structure is designed. The sensitive theory of the acceleration is investigated and the equation of scale factor is deduced under ideal conditions. The simulation is implemented to verify the basic principle by the Ansys and Matlab. The structure simulation results prove that the effective frequency of the torsional accelerometer and the resonator are 0.66kHz and 13.3kHz separately. And the interference modes are isolated with the effective mode apparently. The system simulation results indicate that the scale factor is 37Hz/g and the system has excellent capabilities in locking and tracking natural frequency of resonators, which proves that the basic theory is feasible.

Abstract: A hall speed sensor detection system is designed in this paper. The system consists of the controlling circuit part, the detecting circuit part and the microcomputer part. The system’s structure is simple. It has the advantages such as lower cost, intuitive display and user-friendly. The detecting accuracy can meet the requirements of industrial production, and be suitable for mass production.

Abstract: According to importance of the tool in the modern production,on the basis of tool-flow analysis, this thesis establishes reusable scheduling strategy. In this scheduling, it established a tool information management system based on the central tools magazine. The system includes the main information of each of the tools such as: number, location, usage, current state etc, and for them makes on real-time monitoring and anomalies reporting. Besides a priority mechanism is formulated for multi-tool and multi-task in the scheduling. Finally, the reusable scheduling has been modeling and simulation. To run the emulation program proved that the real-time and effectiveness of the tool management system, and the result of running is analyzed under configurations include the number of different tool, which for the actual production scheduling of tool provides the algorithms and software platforms.

Abstract: In this work, the sensory perception factor was firstly analyzed in infant product based on the great significance of infants cognitive development from the perspective of cognitive psychology. Basically, the corresponding relationship between the development of infant sensory perception and product design elements was researched, aiming at giving a basis for designers to determine the standards for product design and find more potential needs of infants. Then, incorporating a new product of automatic infant soap dispenser, the application of above design method has been further validated of and exploration.

Abstract: A type of tactile sensors based on piezoresistive principle is designed for the robot grab force detection and control. According to human behaves and awareness, the robot grabbing control program imitate human hand grasp active perception and action mechanisms. With the tactile sensors, the slip and grasping process pressure signal is sampled and analysed by general time-domain statistical parameter, and a simpler control algorithm is researched. In the experiment the robot has accomplished soft grabbing by modeling human hand action and applied appropriate grabbing force on objects of different weights or material by means of the control algorithm. Experiments suggest that this sensor and action biomimetic process is suitable to be used in the tele-presence technology application in the case of the visible range or visual equipment aid especially.

Abstract: Compared with single pulse excitation mode, ultrasonic guided wave excited by pulse string is more suitable for long range inspection of rail-break. Shear horizontal (SH) guided wave transducers with modified structure and pulse string emission circuit were designed for the purpose of achieving longer inspection distance. To solve the control difficulty of pulse string, the pulse string phase shift superposition (PSPSS) theorem was proposed and exhaustive algorithm together with genetic-like algorithm were also given to calculate the optimal phase shift parameters. Experiments of pulse string guided wave on rail were carried out. Result shows that the PSPSS theorem can improve wave energy significantly, and the maximum propagation distance of pulse string guided wave can be enhanced up to more than 600 meters.