The spectral relationship between range-rate measurements and the gravity potential for low-low satellite-to-satellite tracking mission was established based on the energy conservation theory. Then the performances of...The spectral relationship between range-rate measurements and the gravity potential for low-low satellite-to-satellite tracking mission was established based on the energy conservation theory. Then the performances of satellite separation, the orbital altitude, and the accuracy of range-rate measurements in recovering the earth's gravity field were simulated and analyzed by this method. Finally, the cumulative geoid errors of the reference mode were obtained by using the configuration parameters of the GRACE mission. By comparing the cumulative geoid errors of the reference mode and GGMO2S and EIGEN-GRACEO2S models, it basically reflected the performance of GRACE and proved the feasibility of this method.展开更多
The nose shape effect on long-rod penetration was investigated by establishing numerical 2D models with different original nose shapes.The variations in nose shapes and the mass erosion rate of the rods in the transie...The nose shape effect on long-rod penetration was investigated by establishing numerical 2D models with different original nose shapes.The variations in nose shapes and the mass erosion rate of the rods in the transient phase,primary penetration phase,and secondary penetration phase were adequately analyzed by two dimensionless parameters,i.e.,the nose shape factor N* and the diameter ratio of the rod nose and shank n.In general,N*,η and the mass erosion rate of the rod vary distinctly in different phases,i.e.,unsteady in the initial transient and the secondary penetration phases,and quasi-steady in the primary penetration phase.Furthermore,a relationship between the mass erosion of the rod and the variation in the nose shape was established.A three-phase 2D model of long-rod penetration was further constructed by considering the variations in nose shape.This research may provide a reference to improve the theoretical model of long-rod penetration.展开更多
基金Supported by the National 973 Program of China (No2006CB701301)the New Century Excellent Talents Plan of Ministry of Education, China(2007)the Open Research Fund Program of Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, China (No.05-08,No.06-12).
文摘The spectral relationship between range-rate measurements and the gravity potential for low-low satellite-to-satellite tracking mission was established based on the energy conservation theory. Then the performances of satellite separation, the orbital altitude, and the accuracy of range-rate measurements in recovering the earth's gravity field were simulated and analyzed by this method. Finally, the cumulative geoid errors of the reference mode were obtained by using the configuration parameters of the GRACE mission. By comparing the cumulative geoid errors of the reference mode and GGMO2S and EIGEN-GRACEO2S models, it basically reflected the performance of GRACE and proved the feasibility of this method.
基金supported by the National Natural Science Foundation of China(Grant Nos.11872118 and 12002293).
文摘The nose shape effect on long-rod penetration was investigated by establishing numerical 2D models with different original nose shapes.The variations in nose shapes and the mass erosion rate of the rods in the transient phase,primary penetration phase,and secondary penetration phase were adequately analyzed by two dimensionless parameters,i.e.,the nose shape factor N* and the diameter ratio of the rod nose and shank n.In general,N*,η and the mass erosion rate of the rod vary distinctly in different phases,i.e.,unsteady in the initial transient and the secondary penetration phases,and quasi-steady in the primary penetration phase.Furthermore,a relationship between the mass erosion of the rod and the variation in the nose shape was established.A three-phase 2D model of long-rod penetration was further constructed by considering the variations in nose shape.This research may provide a reference to improve the theoretical model of long-rod penetration.