Shen H.,Nanjing University of Aeronautics and Astronautics |
Shen H.,Nanjing Research Institute on Simulation Technique |
Yao W.,Nanjing University of Aeronautics and Astronautics |
Qi W.,Nanjing University of Aeronautics and Astronautics |
Zong J.,Nanjing University of Aeronautics and Astronautics
Composites Part B: Engineering | Year: 2017
In this paper an experimental investigation on damage evolution in cross-ply glass fiber reinforced plastic (GFRP) laminates under quasi-static and fatigue loading is presented. Four configurations of lay-up ([02/904]s, [02/902]s, [0/904]s and [0/903/0/903]s) with different thicknesses of cracking plies were selected to study the in-situ behavior in the damage initiation, evolution and saturation. Combined with the imaging features of different damages and the characteristic of damage evolution in the laminates, light transmission method was employed to observe the damage state and to record matrix crack density. In fatigue tests, eight stress levels were chosen for each configuration of laminates, including four lower stress levels below the stress level corresponding to the first transverse crack initiation. A conclusion was drawn from the comparison of the results that the fatigue loading with lower stress level accelerates the process of damage evolution and generates damages more thoroughly at failure. © 2017 Elsevier Ltd
Lv H.,Nanjing Research Institute on Simulation Technique |
Lv H.,Beihang University |
Zhao J.,Nanjing Research Institute on Simulation Technique |
Zhao J.,Beihang University
Journal of Aircraft | Year: 2011
A minimum transmission power loss calculation method is proposed, and the specific load configuration is obtained to improve energy transmission capability of the aircraft electric power system. The method is divided into three steps. First, a node table-style format of the aircraft electric power system is proposed according to its characteristics. Second, the transmission power loss equation is modeled by introducing the power flow calculation method. Third, the system transmission power losses with different load types are studied. Using particle swarm optimization algorithm, the minimum transmission power losses with different system load types are obtained. With the optimum load configuration, the transmission power loss is reduced and energy transmission capacity of the aircraft electric power system will be improved effectively. © Copyright 2010.
Peng Y.-H.,Nanjing Research Institute on Simulation Technique |
Liu D.,Jiangxi University of Finance and Economics |
Lin Y.-Z.,Beihang University
Ranshao Kexue Yu Jishu/Journal of Combustion Science and Technology | Year: 2010
The primary zone flow fields of two types of dome configurations of design A (double swirlers with duplex nozzle) and design B (triple swirlers with pre-filming airblast nozzle)were measured by PIV technology under atmospheric pressure and temperature in order to investigate the effects of the two types of dome configurations on the primary zone flow field of high temperature rise combustor. A single rectangle sector module combustor was used in the experiment for lean blowout under the idle condition, and the pattern factor experiment of high power condition was conducted in a three cups rectangle combustor. The results showed that the pattern factor of design B was improved by 41 percent compared with that of design A, and the fuel air ratio of lean blowout was improved by 13.5 percent compared with that of design A. The performance difference of combustion experiments, including pattern factor and lean blowout, could be analyzed by the PIV results, and the insight relationship between flow field and combustion performance could be found out.
Deng F.,Nanjing University of Science and Technology |
Chen S.-S.,Nanjing University of Science and Technology |
Tan X.-Z.,Nanjing University of Science and Technology |
Xu T.,Nanjing Research Institute on Simulation Technique
Shiyan Liuti Lixue/Journal of Experiments in Fluid Mechanics | Year: 2010
Different tails were designed for canard-controlled long-range missile including no-fins, "T" shaped fins and grid fins, investigated the influence of the long-range missile's aerodynamic characteristics especially the rolling characteristics of different tails at different speeds and attack angles with wind tunnel test. The results indicated that compared with the missile with grid fins, the missile with "T" shaped fins showed good lift characteristics and rolling characteristics in transonic flow, the lift characteristics of the missile with grid fins performance excellent and it's capable of executing the roll control in supersonic flow, and it's important to reduce the drag of grid fins in the future.
Huang Z.,Northeastern University China |
Wang Z.,Northeastern University China |
Lei C.,Nanjing Research Institute on Simulation Technique |
Yan S.,Northeastern University China |
Zhang H.,Northeastern University China
Proceedings of the 28th Chinese Control and Decision Conference, CCDC 2016 | Year: 2016
An optimal control of boost converter based on model-free adaptive controller (MFAC) and fuzzy particle swarm optimization algorithm (FPSOA) is proposed to realize a better response performance and robustness under model mismatch and the parameter time variation. The data-based MFAC is investigated to design the boost converter, which avoids the precise modeling and greatly reduces the influence of model mismatch. Additionally, the FPSOA is used for online optimization of the controller parameters to improve the response performance and robustness. Comparing with the traditional optimal control methods of boost converter, the proposed method avoids the contradiction of establishing accurate model and complex systems design. It inhibits the influences of the parameter time variation and model mismatch, and has a better dynamic and static performance. Finally, the test is implemented on a semi-physical simulation platform for power electronic control systems. The comparison of MFAC and classic state feedback exact linearization control in various model mismatch situations are used to show the effectiveness of the obtained results. © 2016 IEEE.