空间再入充气结构的流固及热固单向耦合研究

As an emerging space technology, inflatable return technology has become a hot spot of space power research because of its large payload ratio, small launch volume, and flexible return. However, the theoretical research on reentrant structures at home and abroad is not mature enough, and the analysis of structural characteristics is not comprehensive. For the description of the nonlinear structural dynamic behavior of a burgeoning inflatable re-entry vehicle (IRVE), the modeling of two-dimensional coordinate system for the IRVE system was presented to calculate the trajectory equation during the reentry process. Half taper angle and initial re-entry angle were optimized by genetic algorithm, and the trajectory was exerted as the boundary condition of CFD simulation to obtain the heat flux distribution. A structural dynamic model of IRVE system was established based on the finite element theory, and the effects of different inflation pressures and film thickness on the static and modal characteristics were investigated. Based on the unidirectional couplings of fluid-solid and thermal-solid, the effects of aerodynamic and aeroheating on static and modal characteristics of IRVE system were studied. The results show that the maximum heat flux decreases with the increase of the half taper angle while rises with the increase of the initial reentry angle. When half taper angle is chosen 57.65° and initial reentry angle is chosen 1.35°, the overload can reach a minimum value of -1.96g. The static characteristic is most affected by aerodynamic pressure when flight height is below 40 km while most affected by aeroheating when flight height is above 40 km.