| At present,the requirements for the working conditions of parachute opening process are constantly improving and the research direction is gradually transitioning from subsonic to supersonic parachute.Under such a trend,this thesis takes the deep space Mars exploration mission as the research background,and the fluid-structure interaction numerical simulation method is used to calculate the dynamic characteristics of the supersonic parachute opening process.Conclusions are drawn by comparing the calculated results with the experiments to provide some engineering reference for supersonic parachutes.Meanwhile,the design parameters of the cruciform parachute are studied on the guidance law of the parachute opening process.And the influence of its ballistic trajectory under different working conditions is analyzed to provide some reference for high-precision landing in future Mars exploration.Firstly,the adopted numerical calculation method is explained in detail,and the proposed method is verified by cases from the aspects of supersonic condition and fluid-structure interaction,which confirms the feasibility of the method.Secondly,the deceleration characteristics of supersonic parachute in the opening process is studied by using the format of space-time conservation element and solution element method(CE/SE)combined with the fluid-structure interaction method of immersion boundary method(IMB),and the opening process of disk-gap-band parachute under three different Mach numbers and three different trailing distance ratio is calculated respectively.Relevant conclusions are drawn through analysis of the structure and flow field result information.The disk-gap-band parachute with Mach number of 2.0 is used as the analysis object,and the test data is compared to verify the accuracy of the calculation results.Finally,the opening process of cruciform parachute is analyzed by the Arbitrary Lagrangian Eulerian method(ALE),and the deceleration characteristics and terminal trajectory stability of cruciform parachute with five different Length-Width Ratios(LWR)under variable wind field of initial trajectory 60° are discussed,and the above method is used to obtain trajectory curves,deceleration characteristic curves and stability curves of the cruciform parachutes under different external conditions. |
