报告题目：Dynamic Modeling of Electric Solar Wind Sail by Hamilton Nodal Position Finite Element Method
报告人：加拿大York University机械工程系主任Zheng H.Zhu院士
Dynamic Modeling of Electric Solar Wind Sail by Hamilton Nodal Position Finite Element Method
Zheng H. Zhu
Department of Mechanical Engineering, York University
4700 Keele Street, Toronto, Ontario M3J 1P3, Canada
The electric solar wind sail (E-sail) is a novel enabling technology for deep space exploration in the solar system. It generalized the propulsion for space travel by extracting energy from a continuous particle stream from the Sun using long and electrically charged tethers. The E-sail possesses rich multi-physics and dynamic characteristics. We have developed a high-fidelity multiphysics model with Hamilton nodal position finite element method to model the coupled large rigid body motion and small elastic deformation of E-Sail and solve the numerical problem with Symplectic integrator in a extra long period. With the model, we investigate the coupling effects of orbital and self-spinning motions of the E-sail, and the interaction between the axial/transverse elastic motions of tether and the Coulomb effect. Furthermore, parametric study is conducted to better understand these coupling effects. Our results show that the coupling effects have a significant impact on the dynamic behavior of E-sail and the induced thrust. Furthermore, analysis indicates a strong dependence of the thrust on the sail/coning angles of E-sail even in the case of small sail angle. Finally, the influence of the initial self-spin rate and sail angle on the dynamic behavior of a flexible E-sail is investigated. Our study also finds that a high spin rate is needed to hold the stable geometrical configuration, and the difference in the orbital maneuvering is distinct when the E-sail inclines to the incident solar wind. It implies that a suitable control strategy should be employed to accomplish the thrust vectoring for the orbit maneuvering. The analysis provides an effective and robust way to design the E-sail in the mission planning phase.
Dr. Zheng H. Zhu is the professor, Tier I York Research Chair in Space Technology of university and Chair of Department of Mechanical Engineering at York University in Toronto, Canada. He received his B.Eng., M.Eng. and Ph.D. degrees in mechanics all from Shanghai Jiao Tong University in China. He also received the M.A.Sc. in robot control from University of Waterloo and Ph.D. in mechanical engineering from University of Toronto all located in Ontario, Canada. His current research interests include dynamics and control of tethered space system, spacecraft rendezvous, space robot and space debris deorbit. He has published over 240 articles and conference papers, with 125 peer-reviewed journal publications. Currently, he is the principal investigator (PI) of two CubeSat missions: DESCENT and ESSENCE, fully funded by the Canadian Space Agency. He is the fellow of Engineering Institute of Canada, Fellow of ASME and CSME, Associate fellow of AIAA, senior member of IEEE, and licensed Professional Engineer in Ontario, Canada. Dr. Zhu is the Editor-in-chief of the International Journal of Space Science and Engineering, Associate Editor of IEEE Access, and serves on editorial boards of many journals.