Influences of the forward rectifier cone on the water entry flow field of the vehicle

The rectifier cone device, which is widely used in the aerospace field, is applied to the front end of the blunt head vehicle. Using the overlapping grid technology, based on the Reynolds Averaged N-S equation, the VOF multiphase flow model is selected, and the Schnerr and Sauer cavitation model is introduced to establish the numerical simulation method of the vehicle's water entry process. The influence of the front rectifier cone pa-rameters on the vehicle's water entry process is analyzed, it provides a useful exploration for the flow field control technology of the Trans-media vehicle. The results show that two types of cavity are formed in the process of entering the water: the small cavity surrounding the rectifier cone and the large cavity surrounding the main vehicle. The size of the small cavity increases with the increase of the length diameter ratio of the rectifier cone, and the shape evolution of the large cavity will deform. Due to the change of cavity type during water entry, the peak value of single impact load will be divided into the peak value of secondary impact load. The rectifier cone with different length diameter ratio can reduce the peak value of impact load on the vehicle by prolonging the impact time of the rectifier cone. Under given conditions, the load reduction rate can reach at least 30% compared with a single blunt head vehicle.