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Journal of Harbin institute of Technology(New Series) 2010年第1期17卷 75-81页

作者：薛亮韩万金 propulsion theory and Technic Academy Harbin Institute of Technology

For a certain type of transonic axial fan, the flow field of a fan rotor with splitter blade was computed by numerical simulation, and the shape of the rotor was modified. The effects of different circumferential distributions concerning the splitter cascades upon the aerodynamic performance were investigated. The studies show that the optimum splitter cascade is not very close to the suction side of main blade. The load between the main blade and the splitter blade can be soundly distributed in terms of the adjustment of circumferential position of the splitter blade. The best aerodynamic performance can be successfully obtained according to the optimum shape of the expanding fluid channel reasonably formed by the splitter blade and the main blade.

关键词： transonic axial fan splitter blade shock wave flow loss compressor

Optimum design of camber line shape in a transonic axial fan cascade with splitter

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Journal of Harbin institute of Technology(New Series) 2008年第2期15卷 290-296页

作者：孙玺淼王松涛姜斌羌小青王仲奇 propulsion theory & Technic Academy Harbin Institute of Technology

Genetic algorithms and artificial neural networks method were adopted to optimize the camber line shape of splitter cascade in a transonic axial fan. For a certain type of transonic axial fan, the isentropie efficiency was improved by 0. 6% with the modification of splitter cascade rotor. Numerical simulation studies show that the curvature of the optimum splitter cascade with larger suction side is increased, the static pressure gradient is reduced, the process of flow expansion on suction surface is controlled and the separation near hub is eliminated by changing the shock wave structure. The efficiency near hub is improved by 1.3%.

关键词： transonic axial fan splitter cascade with splitter camber line optimization

Numerical simulation of 3D viscous flow field of air cooled turbine blades with coolant mixing

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Journal of Harbin institute of Technology(New Series) 2008年第6期15卷 781-785页

作者：姜澎王强黄洪雁冯国泰 propulsion theory and Technology Research Center Harbin Institute of Technology

To improve thrust and reduce oil consumption of aero-engines, the temperature at turbine inlet is becoming higher and higher, which leads to heavy thermal load of vanes. To efficiently cool the vanes, the mass of coolant with its maximum gas mass flow exceeding to 20% of main stream, has to be increased. In the pres- ent paper, a two-stage turbine with and without coolant mixing was simulated by CFX-TASCflow. Simulation resuits indicate that the flow field structure with coolant is obviously different from that without coolant, and the former has characteristics of lower-speed main flow, reduced mach number, weaker shock intensity and decreased stage efficiency.

关键词： gas turbine film cooling mixing multi-stage

Numerical simulation on conjugate heat transfer of turbine cascade

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Journal of Harbin institute of Technology(New Series) 2009年第6期16卷 741-745页

作者：周驰颜培刚姜澎冯国泰 propulsion theory and Technology Research Center Harbin Institute of Technology

Numerical simulation on conjugate heat transfer of an internal cooled turbine vane was carried out. Numerical techniques employed included the third-order accuracy TVD scheme, multi-block structured grids and the technique of arbitrary curved mesh. Comparison between results of commercial CFD codes with several turbulence models and those of this code shows that it is incorrect of commercial CFD codes to predict the thermal boundary layer with traditional turbulence models, and that turbulence models considering transition lead to more accurate heat transfer in thermal boundary layer with some reliability and deficiency yet. The results of this code are close to those of CFX with transition model.

关键词： turbine conjugate heat transfer heat conduction numerical validation

A Test Case Generation Approach Based on Sequence Diagram and Automata Models

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Chinese Journal of Electronics 2016年第2期25卷 234-240页

作者： ZHANG Chen DUAN Zhenhua YU Bin TIAN Cong DING Ming institute of Computing theory and Technology Xidian University School of Computer Science and Technology Xidian University School of Information and Technology Northwest University Xi’an Aeronautics Computing technique Research institute AVIC

To improve the test automation in software development process, following the researches on test cases generation technology from models, an incremental test case generation approach is proposed based on finite automata, and Event deterministic finite automata(ETDFA)are employed to describe the sequence diagram models of system interaction. By model checked with Propositional pro jection temporal logic(PPTL), the correctness of ETDFA is verified. Then we can get the composed automata by synthesis rules, and generate the test cases incrementally by test cases generation algorithm. Case studies are presented to show that this approach enables to improve test cases correctness, and reduce the complexity of test cases generation process.

关键词： Test model Model based testing Test scenario Test cases

Flow Diagnosis and Optimization Based on Vorticity Dynamics for Transonic Compressor/Fan Rotor

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Open Journal of Fluid Dynamics 2017年第1期7卷 40-71页

作者： Huanlong Chen Mark G. Turner Kiran Siddappaji Syed Moez Hussain Mahmood institute of propulsion theory and technique Harbin Institute of Technology Harbin China Aerospace Engineering Department University of Cincinnati Cincinnati OH USA

This paper presents two optimized rotors. The first rotor is as part of a 3-blade row optimization (IGV-rotor-stator) of a high-pressure compressor. It is based on modifying blade angles and advanced control of curvature of the airfoil camber line. The effects of these advanced blade techniques on the performance of the transonic 1.5-stage compressor were calculated using a 3D Navier-Stokes solver combined with a vortex/vorticity dynamics diagnosis method. The first optimized rotor produces a 3-blade row efficiency improvement over the baseline of 1.45% while also improving stall margin. The throttling range of the compressor is expanded largely because the shock in the rotor tip area is further downstream than that in the baseline case at the operating point. Additionally, optimizing the 3-blade row block while only adjusting the rotor geometry ensures good matching of flow angles allowing the compressor to have more range. The flow diagnostics of the rotor blade based on vortex/vorticity dynamics indicate that the boundary-layer separation behind the shock is verified by on-wall signatures of vorticity and skin-friction vector lines. In addition, azimuthal vorticity and boundary vorticity flux (BVF) are shown to be two vital flow parameters of compressor aerodynamic performance that directly relate to the improved performance of the optimized transonic compressor blade. A second rotor-only optimization is also presented for a 2.9 pressure ratio transonic fan. The objective function is the axial moment based on the BVF. An 88.5% efficiency rotor is produced.

关键词： Transonic Compressor Control Curvature Optimization Vorticity Dynamics BVF Azimuthal Vorticity

Target Tracking Algorithm Using Finite-time Convergence Smooth Second-order Sliding Mode Controller for Mobile Robots

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Chinese Journal of Mechanical Engineering 2011年第3期24卷 414-419页

作者： GE Lianzheng ZHAO Lijun GAO Tong State Key Laboratory of Robotics technique and System Harbin Institute of Technology Harbin 150001 China

Target tracking control for wheeled mobile robot （WMR） need resolve the problems of kinematics model and tracking ***-order sliding mode control is a valid method used in the nonlinear tracking control system,which can eliminate the chattering of sliding mode *** there lacks the research of robustness and uncertain factors for high-order sliding mode *** address the fast convergence and robustness problems of tracking target,the tracking mathematical model of WMR and the target is *** on the finite-time convergence theory and second order sliding mode method,a nonlinear tracking algorithm is designed which guarantees that WMR can catch the target in finite *** the same time an observer is applied to substitute the uncertain acceleration of the target,then a smooth nonlinear tracking algorithm is *** on Lyapunov stability theory and finite-time convergence,a finite time convergent smooth second order sliding mode controller and a target tracking algorithm are designed by using second order sliding mode *** simulation results verified that WMR can catch up the target quickly and reduce the control discontinuity of the velocity of WMR.

关键词： mobile robots second order sliding mode finite-time convergence observer

An LMI-based decoupling control for electromagnetic formation flight

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Chinese Journal of Aeronautics 2015年第2期28卷 508-517页

作者： Huang Xianlin Zhang Chun Lu Hongqian Yin Hang Center for Control theory and Guidance Technology Harbin Institute of Technology

Electromagnetic formation flight （EMFF） leverages electromagnetic force to control the relative position of satellites. EMFF offers a promising alternative to traditional propellant-based spacecraft flight formation. This novel strategy is very attractive since it does not consume fuel. Due to the highly coupled nonlinearity of electromagnetic force, it is difficult to individually design a controller for one satellite without considering others, which poses challenges to communications. This paper is devoted to decoupling control of EMFF, including regulations, constraints and con- troller design. A learning-based adaptive sliding mode decoupling controller is analyzed to illustrate the problem of existing results, and input rate saturation is introduced to guarantee the validity of frequency division technique. Through transformation, the imposed input rate saturation is con- verted to state and input constraints. A linear matrix inequalities （LMI）-based robust optimal con- trol method can then be used and improved to solve the transformed problem. Simulation results are presented to demonstrate the effectiveness of the proposed decoupling control.

关键词： Decoupling control Electromagnetic forces Electromagnetic formationflight Linear matrix inequalities Satellite control

Solar Energy Cell with Rare Earth Film

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Journal of Rare Earths 2004年第Z1期22卷 339-341页

作者： Li Baojun Yang Tao Zhou Yao Zhou Meng Fu Xiliang Fu Li institute of Architecture technique Research Shenyang Jianzhu Univercity Shenyang 110016 China

The characteristic of the solar energy cell with the rare earth film according to theory of molecular structure was *** sunlight shines, the molecules of the rare earth film can absorb energy of the photon and jump to the excited state from the basic state, and play a role in storing solar *** sunlight do not shine, the electron of the excited state returns to the basic state, the rare earth film can automatically give out light and shine to surface of the solar cell, which can make solar cell continuously generate electric *** rare earth film can absorb direct,scattering sunlight, and increase density of solar energy to reach surface of the solar cell, and play focusing *** rare earth film can bear 350 ~ 500 ℃, which make the solar cell be able to utilize the focusing function *** after luminescence of the rare earth film, it can release again the absorbed solar energy through 1 ~ 8 h, and play a role in storing solar energy; The solar cell with the rare-earth film can generate electricity during night and cloudy days, and remarkably increase efficiency of the solar cell.

关键词： solar energy rare-earth film cell luminescence

Periodic atomization characteristics of simplex swirl injector induced by klystron effect

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Chinese Journal of Aeronautics 2018年第5期31卷 1066-1074页

作者： Anlong YANG Shangrong YANG Yunfei XU Longfei LI Science and Technology on Liquid Rocket Engine Laboratory Xi'an Aerospace Propulsion Institute

The atomization dynamic characteristics of a simplex swirl injector was investigated experimentally by using a hydrodynamic mechanical pulsator and the shadow photography technique. The frequency response characteristics of the fluid film and atomization fluctuations and their correlations with pressure fluctuations were obtained by using an in-house code of image processing. It is demonstrated that the klystron effect induced by periodic pressure fluctuations results in periodic liquid film fluctuation with large amplitudes, periodic superposition of droplets and reduction of the breakup length. It was found that the atomization of the simplex swirl injector only responds to the pressure fluctuation in frequency range approximately from 0 to 300 Hz, and it is particularly sensitive to pressure fluctuations at frequencies from 100 to 200 Hz. According to this experiment, the responsive frequency limitation is merely affected by injector configuration, rather than the supply line.

关键词： Atomization Combustion stability Klystron effect Liquid rocket engine Simplex swirl injector