Yao Z.-X.,Shenyang Aircraft Design Institute
29th Congress of the International Council of the Aeronautical Sciences, ICAS 2014 | Year: 2014
In this paper, the Least-Squares (LS) method is used for aerodynamic model identification of a scaled UAV designed for researching the high Mach number aircraft. The LS module is composed of State Matrix, Parameter Measure Vector, Parameter Estimate Vector, and Parameter Estimate Covariance, and so on. The equation-error method calculates aerodynamic parameter estimates that minimize squared errors between values of the non-dimensional force and moment coefficients determined from measured flight data, and model values computed from the aerodynamic model based wind-tunnel test data. For conducting the Aerodynamic Model Identification study, the appropriate data are elaborately selected from the whole flight test data based on some rules. Results presented in the paper show that the identification of lift coefficient derivative about Angle-of-Attack agrees well with the aerodynamic model based on wind-tunnel test data.
Zheng G.N.,CAS Institute of Mechanics |
Yang G.W.,CAS Institute of Mechanics |
Qian W.,Shenyang Aircraft Design Institute
Science China Technological Sciences | Year: 2013
A tightly coupled method was developed to analyse aeroelasticity by constructing subiterative schemes for fluid and structural equations of motion, respectively. With MPI partition parallel computing, the fluid was solved by Navier-Stokes equations based on hybrid grids. A new unstructured background grid deformtion method was used for the CFD grid deformation. The transonic flutter wind tunnel model of a complete aircraft was simulated to validate the developed method. The flutter characteristics of the aircraft was analysed and compared with the test results. It indicates that the devoloped method has a relatively higher precision and can be used for aeronautical engineering application. © 2012 Science China Press and Springer-Verlag Berlin Heidelberg.
Zhang P.,Nanjing University of Aeronautics and Astronautics |
Zhou L.,Nanjing University of Aeronautics and Astronautics |
Qiu T.,Shenyang Aircraft Design Institute
Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica | Year: 2011
Morphing aircraft require the airfoil camber to change continuously and smoothly. The flexible skins must have substantial in-plane expansion deformability, while at the same time it must be able to bear the out-of-plane aerodynamic loads. In this article, a new flexible honeycomb structure is designed for the wing with a variable camber trailing edge. The relationship between the in-plane deformability and the shape parameters of the flexible honeycomb are studied. Simulation and experimental studies are carried out for the flexible honeycomb. The results show that the flexible honeycomb has substantial in-plane deformability and maintains good out-of-plane bearing capacity, which satisfies the application requirements of the wing with a variable camber trailing edge.
Li H.-E.,Shenyang Aircraft Design Institute |
Sha A.-X.,Aerospace Research Institute of Materials And Processing Technology
Cailiao Gongcheng/Journal of Materials Engineering | Year: 2010
The effect of strain rate and deformation temperature on the deformation resistance and the microstructure of TC18 titanium alloy was studied through heat simulating test at 700-950°C and strain rate 0.001-50 s-1. The results show that, when the deformation temperature increases or the strain rate decreases, the real stress can be reduced obviously. Comparing to deformation in β phase, deformation resistance in α+β phase is more sensitive to the change of temperatures. When α+β phase deformed, α and β phases join in deformation at the same time, but deformation degree is different. Preliminary equiaxed alpha phase is elongated slightly and beta phase changes to fiber texture along deformation direction. When β phase deformed, beta phase is fibrous along metal flowing direction, and equiaxed beta grain can be seen when the deformed temperature is above 950°C.
Duan H.,Beihang University |
Shao S.,Shenyang Aircraft Design Institute |
Su B.,China Aerospace Science and Technology Corporation |
Zhang L.,Academy of Equipment Command and Technology
Science China Technological Sciences | Year: 2010
Bio-inspired intelligence is in the spotlight in the field of international artificial intelligence, and unmanned combat aerial vehicle (UCAV), owing to its potential to perform dangerous, repetitive tasks in remote and hazardous, is very promising for the technological leadership of the nation and essential for improving the security of society. On the basis of introduction of bio-inspired intelligence and UCAV, a series of new development thoughts on UCAV control are proposed, including artificial brain based high-level autonomous control for UCAV, swarm intelligence based cooperative control for multiple UCAVs, hybrid swarm intelligence and Bayesian network based situation assessment under complicated combating environments, bio-inspired hardware based high-level autonomous control for UCAV, and meta-heuristic intelligence based heterogeneous cooperative control for multiple UCAVs and unmanned combat ground vehicles (UCGVs). The exact realization of the proposed new development thoughts can enhance the effectiveness of combat, while provide a series of novel breakthroughs for the intelligence, integration and advancement of future UCAV systems. © 2010 Science China Press and Springer-Verlag Berlin Heidelberg.