DYNAMIC SIMULATION OF CIVIL AIRCRAFT DITCHING BASED ON CFD METHOD

A numerical simulation was carried out to investigate the dynamic impact for civil aircraft ditching. The simulation used Reynolds averaged N-S equation from the computational fluid dynamics (CFD). Water-air interface and ditching process were modeled through the combination of volume of fluid (VOF) method and full-flow moving mesh. The position and attitude of aircraft were determined by solving 6-degrees-of-freedom equations. Firstly, the method was validated through typical examples, and then it was used for ditching simulation and analysis of a regional aircraft. The tail-mounted-engine and high-tail layout was focused when researching ditching characteristics. The results show that ditching movement and load characteristics can be well simulated. During water entry period, the regional aircraft is subjected to a large water impact load, while the suction force generated by rear fuselage makes the aircraft pitching up. Afterwards, the suction force decreases as speed decreases, and the aircraft gradually pitches down and approaches to a stable state.