Abstract: Glare is a key factor that influencing the visual performance in light conditions of flight deck, and glare source in flight deck is very complex. It is difficult to directly evaluate the complex glare source, such as non-uniform glare, irregular shape glare and indirect glare using current glare equations. In this paper, a novel method based on SPEOS simulation to predict several types of glare is proposed. Simulation of glare scene is carried out using SPEOS software. Glare source is detected by secondary development on SPEOS. Source luminance, background luminance, position index and solid angle of source are calculated by secondary development as well. And then, the desired glare index can be computed. Finally, Unified Glare Rating(UGR) equation is utilized as an example to predict the glare. The results indicate that the proposed method can compute glare index automatically and quickly, and is useful in illumination design of flight deck.
Abstract: This paper presents a method for transient simulation of AC-DC systems. With the pre-simulation technique, the method automatically determines the weight factor for different position in the simulated AC-DC system, so as to compromise the accuracy requirement as well as numerical oscillation reduction. A case was studied to verify the efficiency and accuracy of the proposed methodology.
Abstract: This paper presents OpenMP thread scheduling strategies by studying OpenMP load balance. In addition to analyze the defects of OpenMP load balance, an optimization program is proposed, and the ideas and methods of this program are described in this paper.
Abstract: Vertical vibration is universal in the vertical system of rolling mill. It has a seriously bad effect on the quality of strip. Dynamic model of the vertical system plays an important role in the analysis of vertical vibration in rolling mill. On the basis of 1420mm six roller cold rolling mill, ADAMS rigid model and flexibility model are established in this paper. Contact stiffness of rollers is calculated through ansys simulation. Contact stiffness between the work-roll and strip is calculated by using theoretical methods and stiffness of mill stand is calculated by simplifying mill stand structure. Natural frequency and some amplitude-frequency response of vertical vibration are analyzed. The test results prove that the modeling method is feasible. Vibration derived from the deformation of rolls can be observed directly in the flexible model, which can’t be realized in the rigid body model. At the same time, the new method of calculating vertical system stiffness is also proved to be reasonable.
Abstract: Combustion control is the most important aspect in boiler unit operation, while the boiler air flow monitoring is the main content of combustion monitoring. Therefore, real-time and accurate online monitoring of the air flow in boiler main and branch pipes is of great importance for the economy, safety and environmental protection of the boiler combustion. This paper mainly introduces an air flow on-line monitoring system in utility boiler based on AC induction. By using the international advanced AC charge-coupling technology and digital signal processing technology, it overcomes the present technique difficulties of air flow on-line monitoring system. It has the advantages of high measuring accuracy and easy installation and maintenance. Also, it is applicable to the air flow on-line monitoring in different types of air ducts, therefore, it can bring certain economic benefits and have the prospect of popularization and application.
Abstract: This paper presents a new contact model to describe the contact constraints for heavy-duty manipulation. This contact model considers the contact area as a surface, which can translate three-dimension forces and torques. The contact deformations which are resulting from the large contact forces cannot be ignored. Distributed linear elastic contact model is adopted to describe the relationship between contact force and contact deformation. A case study is carried out in this paper based on this contact model for the grasp force analysis of heavy-duty manipulators.
Abstract: Three-dimensional magnetohydrodynamic(MHD) model of vacuum arc was built based on two-fluid model of ion and electron and Maxwell equation. In the MHD model mass conservation equation, momentum conservation equations, energy conservation equations of ion and electron, electric potential equations and magnetic equations were considered. With the aid of Computational Fluid Dynamics(CFD) software FLUENT and Re-development by visual C++, the important plasma parameters of low current vacuum arc , such as axial current density , ion temperature, electron temperature, mach number, were analyzed. The simulation results shown that the distribution of plasma parameters is consistent with that of the 2D axis-symmetric model.
Abstract: As one of the national medium-long term energy conservation special planning, the energy efficiency for motor system is key projects. On the other hand, a large number of motor systems have a wide range of applications in power system, and almost occupy 60 percent of the end use energy consumption. It is very important to improve motor system energy efficiency for end use energy efficiency improvement. This paper introduces the energy efficiency evaluation methods and testing system for motor and the high-efficiency motor, by the system, energy conservation certification evaluation and energy label technology service are given, thus, the motor efficiency can be known by the testing. The system can help manufacturers and users to make right decision during the models producing and selecting, and it can be meet the technique requirement of the smart grid construction.
Abstract: Permanent-magnet linear synchronous motor (PMLS-M) exist the problem of normal force fluctuation, especially in the servo feeding system of high-precision CNC machine tools, the normal force fluctuation can cause the feeding table in vibration and produce resonance with other moving components of the servo feeding system .Analysis shows that detent force fluctuation is the predominant factor. Adopt the methods of end-teeth optimization combine with skew or V-skew can effectively reduce the detent force fluctuation. By using the Fourier regression analysis and limited enumeration method to calculate the optimal parameters, and applying the layered finite element analysis for simulation. The results of simulation prove that with the precondition of the thrust force loss slightly, adopt those optimization methods can reduce the normal force fluctuation significantly.
Abstract: Simulation systems with hardware-in-loop are composed by three-Axis virtual flight motion simulator, simulation computer, load torque simulator, and visual simulation systems. Three-Axis Virtual Flight Motion Simulator are used to simulate the attitude of missile in simulation system with hardware-in-loop, so its performance influenced the result of simulation directly. This paper mainly analyzed the factors which influenced the performance of a three-Axis virtual flight motion simulator which we are used now in the lab, then analyzed the entire simulation system’s error caused by these factors through numerical simulation method. By analysis we can see that bandwidth is the main factor influenced the precision of simulation systems with hardware-in-loop, mechanical device installation error and measurement error may also cause some errors of the systems at the same time.