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Wang Y.-F.,Harbin Institute of Technology | Wen F.-B.,Harbin Institute of Technology | Wang S.-T.,Harbin Institute of Technology | Zhou X.,Harbin Institute of Technology | Liu X.,No703 Research Institute Of Csic
Kung Cheng Je Wu Li Hsueh Pao/Journal of Engineering Thermophysics | Year: 2017

In order to decrease the axial length and enhance the thrust-weight ratio of the aero engine, a 1+1 counter-rotating turbine has been redesigned into a 1+1/2 counter-rotating turbine by fully 3D design method with coolant flow taken into consideration, and the internal flow field has been analyzed. The result showed that newly designed 1+1/2 counter-rotating turbine achieves the performance of the original turbine with an acceptable efficiency, and decreases the blade number and axial length of the turbine at the mean time. In addition, issues like through flow design and blades matching under high coolant flow rate condition, shock wave control of high exit Mach number, blade profile design of high inlet Mach number and influence on cooling effect by passage vortex in high-loaded turbine passages should be taken into consideration during designing process. © 2017, Science Press. All right reserved.


Wang W.-Y.,Harbin Engineering University | Li S.-Y.,Harbin Engineering University | Wang J.-F.,China National Offshore Oil Corporation | Cui B.,No703 Research Institute Of Csic
Reneng Dongli Gongcheng/Journal of Engineering for Thermal Energy and Power | Year: 2016

For the problems of compressor performance degradation and regular cleaning maintenance caused by compressor fouling in the actual operation process of gas turbine, the paper develops a prediction approach based on time series model for gas path performance degradation of gas turbine. On the basis of gas turbine thermal modeling and simulation, taking exhaust gas temperature of gas turbine as an example, the paper conducts the validity evaluation on the application of time series model in the prediction on gas path performance degradation of gas turbine. The study results indicate that by using the approach, the prediction on the changes of the gas path performance parameters of gas turbine can be transformed into the time series prediction problem. In this way, the prediction on gas path performance degradation of gas turbine can be realized effectively, and then cleaning maintenance as appropriate for compressor can also be implemented. The approach provides a new way to online condition monitoring and fault diagnosis for gas turbine, so it has a certain engineering application value. © 2016, Harbin Research Institute. All right reserved.


Xue X.,Harbin Institute of Technology | Zhou X.,Harbin Institute of Technology | Liu X.,No703 Research Institute Of Csic | Wen F.,Harbin Institute of Technology
Proceedings of the ASME Turbo Expo | Year: 2016

The pitch-wise uniformity of inlet flow was proved by experiment in low-speed plane cascade, and simulations were performed for investigation and improvement in this study after that. The deflector, which was connected to the blade strictly, was proved to be the cause of the problem according to the simulation, and unexpected inflection of inlet flow were proved at the same time. It was also proved that a gap, which was placed between the blade and the deflector, could weaken the influence of deflector. However, the leakage that caused by the gap would also lead to some negative effects that attentions must be paid to. Finally, with cascade moved half-pitch along x-axis and one extra blade added, more acceptable result between 1 and 4 relative pitch-wise was showed in one of the improved cases (Case B). Better inlet condition with more periodic pressure distribution and acceptable incident angle were gained. © 2016 by ASME.


Wang Y.,Harbin Institute of Technology | Zhou X.,Harbin Institute of Technology | Liu X.,No703 Research Institute Of Csic | Wang S.,Harbin Institute of Technology
Proceedings of the ASME Turbo Expo | Year: 2016

As part of our efforts to understand better ways and means to further improve jet engine performance, the influence of trailing edge coolant ejection rate and cut-back length on energy loss and shockwave intensity of a transonic turbine blade is numerically investigated with an exit Mach number of 1.2 for different coolant/main stream mass-flux ratios and cut-back lengths. Test results indicate both coolant ejection rate and cutback length have their optimum values, and the best ejection rate and the best cut-back length correlate with each other. From the view of minimizing the energy loss coefficient, the best ejection rate decreases with the increasing cut-back length. And from the view of minimizing the trailing edge shockwave intensity, a higher trailing edge coolant ejection rate and a longer trailing edge cut-back can reduce the shockwave intensity. It is therefore believed that these findings can of course facilitate the design of a trailing edge cooling system for transonic turbine blade to further improve jet engine performance. Moreover, trailing edge coolant ejection can be considered as an active flow control method at the same time. © 2016 by ASME.


Zhang L.,Harbin Institute of Technology | Du X.,Harbin Institute of Technology | Liu X.,No703 Research Institute Of Csic | Wang S.,Harbin Institute of Technology
Proceedings of the ASME Turbo Expo | Year: 2016

Aspirated compressor is a promising design concept to promote the working capacity of compression system and thus may result in an intensive interactions with adjacent rows, however, few extensive unsteady flow analysis have been conducted on this type of highly-loaded compressor. This work presents a three-dimensional numerical simulation of a low speed 1.5 stage low-reaction aspirated compressor (LRAC). The boundary layer suction is only implemented in the outlet vane to control the corner stall and boundary layer separation while no active flow control method is applied in the rotor. The total aspiration flow rate is around 3%. Both aspiration slot and plenum were integrated into the computational domain. Two operating points were selected with the aim to investigate the unsteady effects on the performance of the LRAC and to provide a preliminary unsteady description for this type of aspirated compressor. It is found that compared with the differences in 1D total aerodynamic parameters, evident departures are found in the radial distributions of stage outlet flow parameters between the steady and time-averaged results. For the unsteady case, the radial distributions of pitchwiseaveraged parameters become more uniform due to the redistributed aspiration flow rate and the convection behavior of the rotor wake. For the aspiration scheme in the blade, although one-side-aspiration manner is applied, the aspiration flow rate presents a C-type distribution in the radial direction, and this tendency becomes more prominent for the forward slot and time accurate results. Besides, the fluctuation of aspiration flow rate is mainly focused on the upper span due to the intensive rotor outlet secondary flow here. Moreover, the potential effect of aspirated stator on rotor is also examined preliminarily. It is found that for the LRAC investigated in this paper, the rotor suction side is apt to be influenced by the downstream aspirated stator. Finally, some suggestions on the design of the aspirated compressor are provided. © 2016 by ASME.


Kang L.,No703 Research Institute Of Csic | Xu W.,No703 Research Institute Of Csic | Zhang Y.,No703 Research Institute Of Csic | Zhou R.-J.,Grand New Power Co.
Reneng Dongli Gongcheng/Journal of Engineering for Thermal Energy and Power | Year: 2016

The numerical analysis on four kinds of stator blade including evenly-loading blade, positive-curving & evenly-loading blade, aft-loading blade and positive-curving aft-loading blade was made under the same boundary conditions, and the air test of the annular cascade test pieces of the positive-curving & evenly-loading blade was carried out on the wind tunnel test bench with outlet Mach number of 0.97. The study results showed that positive-curving blade can control effectively the secondary flow of tip section, realize the homogenization of the loss at the radial direction and make the Mach number contour orthogonal to the central line of the flow channel. Under the same boundary conditions, for both the evenly-loading blade and aft-loading blade, effective positive-curving can make the total pressure recovery coefficient increased by more than 1%. © 2016, Harbin Research Institute. All right reserved.


Yang Z.,Harbin Engineering University | Wang Y.,No703 Research Institute Of Csic | Liu Z.,Harbin Engineering University
Proceedings of the World Congress on Intelligent Control and Automation (WCICA) | Year: 2015

The paper studies the formation control problem for multiple underactuated surface vessels by utilizing leader-follower approach with parameter uncertainties and external disturbances, and the proposed formation control method that the follower tracks a reference trajectory based on the leader's position and the predetermined formation without the need for leader's velocity and dynamics. A virtual ship is constructed such that its trajectory converges to the reference trajectory of the follower in limited time. The Ships formation control model is established on the virtual ship under leader-follower mode. The robust controller can effectively deal with parameter uncertainties and external disturbances by combining backstepping with sliding-mode control method, which can make the follower move along the trajectory of the virtual ship, maintain the desired formation with leader and achieve the purpose of formation control. A Simulation of the formation control for the multiple underactuated surface vessels is performed by using three real Northern Clippers. Results validate the effectiveness of the proposed method. © 2014 IEEE.


Zhu Z.,Nanjing University of Aeronautics and Astronautics | Zhu Z.,Anhui University of Science and Technology | Zhu R.,Nanjing University of Aeronautics and Astronautics | Li Y.,No703 Research Institute Of Csic | And 2 more authors.
Jixie Gongcheng Xuebao/Journal of Mechanical Engineering | Year: 2012

By means of the coordinate transformation, the equivalent displacement formula of the gear installation errors along the mesh lines for the encased differential herringbone train is deduced. Based on the theory of the concentrated parameter, a dynamics model of this train which adopts the intermediate floatingcomponent is set up. Through calculation of the load sharing coefficients of the internal and external mesh in the 2-stage, the curves of the relationships between the gear installation errors and the load sharing coefficients of the internal and external mesh are obtained and the impact of installation errors on the load sharing characteristic is analyzed. The research results show that under the action of the gear installation errors the load sharing coefficients in the differential stage are bigger than that in the encased stage. In the differential stage, the load sharing coefficient of the internal (external) mesh increases with the installation error of the internal (sun) gear, the installation error of the internal (sun) gear has very small impact on the load sharing coefficient of the external (internal) mesh. In the encased stage, the load sharing coefficients are bigger with the installation error of the internal gear, the installation error of the sun gear has minor effect on that. The installation error of the planet (star) gear has lesser influence on the load sharing coefficients in the differential (encased) stage. The load sharing coefficients in the differential stage are not sensitive to the position angles of the installation errors of the center gear, but the position angles of installation errors of the center gear in the encased stage have bigger influence on the load sharing coefficients. © 2012 Journal of Mechanical Engineering.


Yang Z.,Harbin Engineering University | Liu F.,Harbin Engineering University | Wang Y.,No703 Research Institute Of Csic
Ship Building of China | Year: 2015

In order to realize the path following control for underactuated surface vessels under parameter perturbation and external disturbances, a neural and sliding mode controller is presented based on visible distance. Desired position and current position are used to determine reference surge velocity and yawing angle, which are employed as virtual control laws in stabilizing position errors. Based on neural network and sliding modes, a new nonlinear feedback robust controller is designed, and then the tracking control of the laws of virtual control can be realized without determining upper bound of parameter perturbation and external disturbances. The problem of saturation and chattering of the controller are circumvented. Simulation experiments indicate that the controller is robust against parameter perturbation and external disturbances. Moreover, the path following control can be achieved with the proposed control method. ©, 2015, Editorial Office of Shipbuilding of China. All right reserved.


Qian T.,Harbin Engineering University | Li Y.,Harbin Engineering University | Zhang J.,No703 Research Institute Of Csic
Asia-Pacific Power and Energy Engineering Conference, APPEEC | Year: 2012

A 149 tubes simplified physical model is established by reasonable simplified assumed conditions. The basic differential equations of fluid flow and heat-transfer are obtained on the base of the thermodynamic process of superheater heat transfer. Spatial distribution of thermodynamic parameters under steady-state and dynamic working process is achieved directly by simulating the whole superheater system (gas, steam and wall). Therefore, the internal working principles of boiler system are revealed. © 2012 IEEE.

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