Yang C.,Avic The First Aircraft Institute |
Zhang J.,Nanjing University of Aeronautics and Astronautics
Chinese Journal of Aeronautics | Year: 2012
A series of computations is conducted for many multi-hole arrangements at several blowing ratios to further investigate the evolution of the film from multi-holes. The influence of multi-hole arrangement on effusion film cooling is analyzed and a preliminary relationship evaluating the film development from developing state to developed state is brought forward. Results show that the coolant jets from front rows of multi-holes merge rapidly and the strength of the kidney vortices due to mainstream-coolant jet interaction in the downstream region are mitigated under super-long-diamond arrangement where the streamwise hole-to-hole pitch is bigger than spanwise hole-to-hole pitch. The holes array arranged in super-long-diamond mode is not only in favor of obtaining developed film layer, but also improving averaged adiabatic film cooling effectiveness. © 2012 Chinese Journal of Aeronautics.
Wang X.M.,Northwestern Polytechnical University |
Wang Y.F.,Avic The First Aircraft Institute |
Lu Z.Z.,Northwestern Polytechnical University |
Deng C.H.,Xian Aerospace Propulsion Institute |
Yue Z.F.,Northwestern Polytechnical University
Mechanics of Materials | Year: 2010
This paper presents the results of a series of experiments to investigate the superelastic cyclic stress-strain responses of NiTi shape memory alloys under tension-torsion biaxial loading conditions. The uniaxial tension and torsion experiments were also conducted to make comparisons. Experiments were controlled by axial displacement and torsional angle in sine wave form with fixed maximum values. Saturation is reached after 30 cycles. The evolutions of equivalent stress-strain curves as well as the separated tensile and shear stress-strain curves during cycling are analyzed. Dissipated energy density, characteristic stresses and strains as functions of deformation cycles are paid attention. Results show that the mechanical responses are significantly affected by the loading path. The stress-strain behaviors under proportional loading are similar to those under uniaxial loading. With the increase of the out-of-phase angle during the non-proportional loading, the special phase transformation exhibition totally disappears in the equivalent stress-strain curves. © 2009 Elsevier Ltd. All rights reserved.
Liang B.,Northwestern Polytechnical University |
Li Y.,Northwestern Polytechnical University |
Li R.,Avic The First Aircraft Institute
Journal of Computers | Year: 2011
With the background of the development of Aircraft Anti-skid Braking System, a new aircraft Electro- Hydrostatic Actuator (EHA) of a certain model fighter is designed to meet the need of the braking system. The paper describes the principle of work and features of the EHA, and gives the specific requirements of the system. The selection and performance of the motor, pump and hydraulic cylinder are optimized. Then, the paper describes the principle of work and features of the EHA, models and simulates it with MATLAB/Simulink., and analyzes the effects of all structural parameters on the performance. The results of EHA reach the design target of dynamic performance. Finally, the whole model of the aircraft system is built and established based on the EHA model and results. The results of the dry runway condition verify the correctness of the EHA design, so the Hydro Actuator of traditional aircraft anti-skid braking system could be replaced by EHA. © 2011 ACADEMY PUBLISHER.
Yang C.,Beihang University |
Huang C.,Beihang University |
Wu Z.,Beihang University |
Tang C.,Avic The First Aircraft Institute
Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica | Year: 2015
The aeroservoelasticity (ASE) problems occurring on the aircraft (e.g. airplanes, missiles) originate from the sophisticated coupling between aerodynamics, structural elasticity and control system. As the aircraft develops to be lighter, faster and more capable, these problems become increasingly acute and thus have a direct influence on flight safety and performance. After more than sixty years of research, great progress has been made at home and abroad in the field of ASE analysis, synthesis and test. In the recent decade, several new issues are revealed due to the design evolution of aircraft with unconventional configuration, and pose the huge challenges to ASE research, which is worth analysis specifically. This paper discusses the problems of rigid/elastic interaction, nonlinearity, thrust vectoring and system identification in ASE analysis, and states the key issues for gust alleviation, active flutter suppression and ASE optimization in the ASE synthesis. Technologies that need to be focused in ASE tests are emphasized, followed by a brief introduction to some representative examples of overseas ASE tests in the recent decade. Some new directions towards advanced ASE research are indicated, and also suggestions are provided for domestic ASE research. ©, 2015, AAAS Press of Chinese Society of Aeronautics and Astronautics. All right reserved.
He C.-W.,Avic The First Aircraft Institute
AIAA Flight Testing Conference, 2015 | Year: 2015
This paper presents a method for optimized calculation forces for a full-scale aircraft structure fatigue test that attempts to match aerodynamic and inertia nodal forces rather than shear moment and torque diagrams. Application of method to the full-scale fatigue test of one aircraft structure is described; and details process of method is provided. It is shown that the method can produce an equilibrium for aircraft structure while providing a more realistic load distribution. © 2015, American Institute of Aeronautics and Astronautics Inc, AIAA. All right reserved.