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The drag-type vertical axis wind turbines (VAWTs) have advantages of simple structure, self-starting at low wind speed and low cost, but they show low wind energy conversion efficiencies. A novel vertical axis wind turbine is proposed aiming to improve the disadvantage of the traditional wind turbines based on bionic principle in this paper. The structure of the novel vertical axis wind rotor is designed by combining traditional Savonius wind rotor structure and fish's ridge structure. Aerodynamic performance of the novel wind rotor and a traditional Savonius wind rotor are numerically explored and predicted by numerical simulation method for their non-linear two-dimensional unsteady flows. Performance comparison of the two wind rotors is also carried out. The results show that the novel wind rotor has better performance for torque and power coefficient on lower tip speed ratio (TSR) conditions than traditional Savonius rotor. Based on the simulation analysis of the two different types of wind rotors, we present the approach of changing and reconstructing different curvatures to obtain higher efficiency.

To develop the control system of multi-range hydro-mechanical continuously variable transmission (HMCVT), a model of a multi-range HMCVT is built using the principle of dynamics. According to the characteristic of power split, HMCVT is separated as axes set, variable displacement pump-motor system, clutch set. With wheel tractor as application instance, the whole model of vehicle power train is made, which includes the engine, HMCVT, running system and control system. Based on the theory of Finite State Machine, an automatic control method of speed change and range shift is present, which employs the throttle value, engine speed, range number and transmission ratio as the control parameters. The dynamic characteristic of automatic speed changing and ranges shifting is simulated. The result indicates that the model can correctly represent the dynamic characteristic of HMCVT, the engine can run at the optimal working point, the multi-range HMCVT can shift range steadily and change transmission ratio continuously when the load changes, the circularly shift range is avoided. The model can be used conveniently for the analysis of vehicle dynamic performance and the research of multi-range HMCVT control method.

Based on the hydro-mechanical continuous variable transmission (HMCVT) of 400 house-power of Dongfanghong, the synchronization in period of contions to content to multiple period of HMCVT was established by analyzing its transmission principle, and the relation fomulas of power distributing ratio and efficiency was presented. That results showed that the characteristics of power flow at the first half and at the second half were different, when it was within the certain grade to do the boundary of e equaled with zero; while it was each grade in section points, that characters were the same; the more grades, the greater HMCVT system transmitting power and the higher the transmission efficiency of the entire system. The high efficiency features of multiple range hydro-mechanical stepless transmission, meet the requirement of tractor operation.

In this paper, a robot handling system was developed with the functions of visual positioning and position adjustment by using the MOTOMAN-SV3X robot. System components, workflow, robot pose and the method of solving the problem of pick-up position deviation were detailed. An automated and flexible application program was provided for robot handling technology, and the problem that there was pick-up position deviation in the process of transporting workpiece can be effectively resolved, thereby handling precision and efficiency can be improved.

Coal gas accident is the main threat to the safety production in coal mine,it needs a safe and efficient drilling equipment to detection and drainage in the gas area.At present,the equipments detect and drainage in underground coal mines are mainly fission rigs,which move time-consuming, and the efficiency of drilling is low.This paper introduces a new kind of full hydraulic drill car used in coal,it includes the integral design of the car, the structure layout, the drilling arm and the main parts of design ideas.The new drill carriage adopts the caterpillar vehicle structures,full hydraulic pressure drives,it can automatically change the drill rod, prevent bit-stuck device,can freely passage in the narrow roadway,arrived at the reservation of the drilling position and carries on the omni-directional drilling,it can meets various mine construction requirements, and it has a broad market prospect.

In view of the processing characteristic of large equipment, The CNC system of the fine milling machine tool for the large double-sided of aluminum ingot is designed, the hardware of the system is introduced, the software is illuminated mainly, the system is configured based on SCOUT, and the control programs of the manual and automatic processing are designed. Based on WINCC Flexible, the operating system which can meet the multi-interface easy to operate and live real-time monitoring is designed. As the result of the commissioning, the system is stable and reliable.

In this paper a PLC control system is designed to control the sorting, transmission and loading/unloading in the manufacturing, in view of the defects of the relay control system which usually has poor reliability and bad flexibility in use. On the basis of the superior performance of PLC control system and the working principle of frequency converter, AC transducer drive technology is applied to achieve stable starting, reliable operation and low breakdown rate in the assembly line of manufacturing. In the design of the upper monitoring system, the functions of parameter settings, process monitoring and control, data processing, fault location can be well implemented via configuration software. The research work of this paper will lay a solid foundation for the design of material automatic sorting system based on the PLC controller.

This paper mainly introduces the principle of preparation for nano-materials via vapor-phase technics, the design and assembly of nano-material synthesizer. Vapor-phase techniques include physical and chemical vapor synthesis, which involves vapor particle nucleation, nuclei growth, cohesion and a series of basic process in particle growth. Based on the principle of vapor-phase, this paper also details the invention of the process equipment for nano-material synthesis, which realizes an adjustable process in automatic control. The design aims to achieve a synthesizer being adjustable, automatic, intuitive and easy to operate. It mainly includes the following features. First, the invention helps show that preparation for nano-materials via vapor-phase technics is feasible. Second, with the high output of vapor-phase reaction, the synthesizer can not only be carried out in the experimental environment to demonstrate the synthesis of nano-materials, but also be applied in industrial production.

Automobile traffic has become the financial, entertainment, office and communications function as one of the mobile sites. In automotive design and manufacturing and modification, eliminating the noise of car audio systems to improve driving safety and the occupants enjoy audio and video quality is very important. This paper analyzes the car audio system composition, explains automobile noise is divided into mechanical noise and circuit system inner noise, circuit system noise inside mainly includes thermal noise, induction noise and transmission noise, and puts forward the relevant measures to reduce noise.

In this paper, we introduce a new test method for friction performance of wind turbine pitch bearing. Four loading devices are used to put on load on the pitch bearing from different directions through load board. It can accurately simulate the axial force, radial force and overturning moment of wind turbine pitch bearing. The data acquisition device can measure the value of speed, torque and actual output load of loading hydraulic cylinder. After analysis and calculation, the influence of additional friction torque produced by loading device can be obviated, the friction torque of wind turbine pitch bearing under different loads can be test accurately in the laboratory. The research shows that the structure of test bed is compact, mechanical rigidity is good, the replacement of bearing model is expedient. It puts on load easily and can measure the frictional torque of wind turbine pitch bearing under different loads more accurately. It can provide data for performance analysis of wind turbine pitch bearing and ensure the pitch bearing satisfying the application requirements.

High-voltage converter technology applied in coal mining ventilator could gain a great deal of operating effectiveness and economic benefits. This paper illustrates the reformation of main ventilation system in some coal mine of Shanxi province. The defective operation conditions of previous mining ventilator and the advantage of converter control system applied in the mining ventilator are also proposed by this paper. The mathematical model of direct torque control (DTC) method used in the system is analyzed by giving dynamic model of stator flux oriented. The transformed design of converter control system with the benefits of highly enhanced energy-saving and environmental protections is involved as well as its operating statistics on energy-saving effect.