Advanced Materials Research Vol. 619

Abstract: This paper presents a data collection system based on C8051F040 processor and real-time embedded operating system uC/OS-III. The hardware part design, uC/OS-III transplant process and notes, system processes are discussed in detail. This system takes the modular design ideas and reasonable task-assigned strategy, make software is easy to code and modify, realizes real-time, high speed data acquisition.

Abstract: In order to ensure the safety and stability of coal mine main fan’s operation, the system uses programmable controller PLC as the control core, uses integrated transmitter, the man-machine interface touch screen and PC configuration software, achieving real-time monitoring and state control of the main fan’s performance, state parameter, electrical parameter, and uses PowerBuilder 9.0 system development software to build the fan’s fault diagnosis expert system, realizing the comprehensive fault diagnosis of the fan, providing accurate expert advice and repair scheme. It uses advanced Ethernet technology to realize the communication between PC and scene control system. The realization of the main fan’s automation management ensures the stability and reliability of the fan’s running.

Abstract: In order to effectively protect hoist brake shoe′s braking performance, improve the work reliability and service life, establishing temperature monitoring system of hoist brake shoe in braking process.This system consists of detection system and alarm, communication lines, host computer, etc., can be for hoist brake shoe online measurement temperature and real-time monitoring, with low energy consumption, small size, reliability and stability, information processing ability and other characteristics.The system for staff to provide effective reference data, can be according to the monitoring results related parameters in the fixed, ensure brake shoe under the premise of performance improved the safety and reliability of the brake system.

Abstract: Dislocation distribution functions of mode I dynamic crack subjected to two loads were studied by the methods of the theory of complex variable functions. By this way, the problems researched can be translated into Riemann-Hilbert problems and Keldysh-Sedov mixed boundary value problems. Analytical solutions of stresses, displacements and dynamic stress intensity factors were obtained by the measures of self-similar functions and corresponding differential and integral operation. The analytical solutions attained relate to the crack propagation velocity and time, but the solutions have nothing to the other parameters. In terms of the relationship between dislocation distribution functions and displacements, analytical solutions of dislocation distribution functions were gained, and variation rules of dislocation distribution functions were depicted.

Abstract: This paper describes particularly the design and research of an ultra-low-power data acquisition system. It uses LPC2132 as micro controller along with LCD display module and the data communication module, and uses the embedded operating system μC / OS-II to manage the communication and switching between tasks. This system realizes the function of real-time acquisition and display in analog signal and digital signal, and if necessary, the data will be sent to the host computer. The system runs stable, low power consumption and easy to carry.

Abstract: Through the analysis of the flow characteristics of the high-speed solenoid valve, the conclusions that the PWM signal duty ratio is the main factor affecting the solenoid valve flow is obtained, a new available any PWM pulse signal and control circuit are proposed. Further, circuit schematic is simulated by means of SIMULINK tools in MATLAB environment and Verify its stability. A time-sharing drive circuit is design based on the PWM drive mode. The driver circuit have function which is high-current open, small current maintain. Open current and maintain current of Solenoid valve can be adjusted through this circuit. Therefore, the circuit can adapt to different parameters of the solenoid valve. A wide range of applications.

Abstract: wind power is the most effective form of wind energy utilization, modern large-scale wind turbine with horizontal axis wind mainly. Horizontal axis wind turbine aerodynamic performance calculation of the wind turbine aerodynamics research hot spot, is a wind turbine aerodynamic optimization design and calculation of critical load. Horizontal axis wind turbine airfoil aerodynamic performance of the wind turbine operation characteristics and life plays a decisive role". Using Fluent software on the horizontal axis wind turbine numerical simulation, analysis of the United States of America S809NREL airfoil aerodynamic characteristics of different angles of attack numerical simulation, analyzes the different angles of attack in the vicinity of the pressure, velocity distribution. By solving the two-dimensional unsteady, compressible N-S equations for the calculation of wind turbine airfoil S809used the characteristics of flow around. N-S equation in body-fitted coordinate system is given, with the Poisson equation method to generate the C grid.

Abstract: Our country has abundant coal resources, thin seam can reserves 20% of all can be occupied. But , with adverse circumstances, thin coal seam mining has not yet been fully realized automation. Plough is a kind of mining equipment with shallow-frustum, Low mining height, multi circulation.Its simple structure in thin coal seam mining is a unique advantage. Along with the plough development to high-powered, high speed to dig, automation direction, and with its reliable performance problems appear more prominent, it is badly in need of further research and discussion. In order to improve the reliability of plough, expand the scope of use plough, this paper applied the method of virtual prototype of the plough structure strength analysis. Taking a coal company designed BT plough as project object, the joint simulation environment is been established by Pro/E,ANSYS and ADAMS.by using corresponding modal interface technology. At last rigid-flexible coupled model has been formed in ADAM.

Abstract: According to the traditional method of rolling bearing’s life calculation, the paper analyses the existing problems and calculative inaccuracy of it, puts forward the method of calculating the rolling bearing’s life by using basic Fuzzy reliability theory and establishes the model of calculating rolling bearing’s fuzzy reliability Life. Calculating the rolling bearing’s life by using Fuzzy Mathematics overcomes the shortcoming of traditional calculation. It is closer to objective reality.

Abstract: The life support system is the important component of the refuge system, and the air circulation amount is an important parameter of the life support system. So far, the correlation theoretical model between the air circulation amount and the diameter and the rotation speed of the fan impeller has not been established yet, hence the theoretical support of the selections of the diameter and the rotation speed of the fan impeller for given air circulation amount can not be obtained. Therefore, the air circulation amounts with various diameters and various rotation speeds of the fan impeller are simulated by Fluent based on the blade style of an actual fan impeller, and TableCurve 3D is applied for the data fitting of simulation result in 3D surface, the data calculated by the fitting equations coincide with the simulation result. Thus, the fitting formula presented by the paper could provide the theoretical basis for the selections of the diameter and the rotation speed of the fan impeller with the variation of the air circulation amount.