Investigation Of Water-entry Cavity Flow Field Characteristics Of Supercavitating Projectile In Wave Environment

Based on the supercavitating drag reduction technology,the supercavitating projectile can still maintain a high speed after traversing a certain underwater distance,so as to achieve effective attack on underwater targets.Therefore,supercavitating projectile has also become a hot spot in the research of underwater weapons in various countries.At present,the research on the water-entry of supercavitating projectile is mainly in the hydrostatic environment,but less in the wave environment.With the increasingly prominent status of amphibious firearms,the research on the water entry of supercavitating projectile in wave environment is more in line with the actual situation of weapon operation and has great engineering significance.Therefore,this paper mainly focuses on the research on water-entry cavity flow and motion characteristics of supercavitating projectile in wave environment.The investigation is carried out from the following aspects: investigation of prediction method of multiphase coupling mechanical characteristics of supercavitating projectile in wave environment,investigation of water-entry cavity flow and motion characteristics of supercavitating projectile in hydrostatic environment,and investigation multiphase coupling mechanical characteristics of supercavitating projectile in wave environment.The main research contents and research results are as follows:（1）Investigation of prediction method of multiphase coupling mechanical characteristics of supercavitating projectile in wave environment.Based on the overset mesh technique,the multiphase coupling mechanical characteristics of supercavitating projectile in wave environment was established by using RANS equation,Schnerr-Sauer cavitation model,Realizable k-ε turbulence model and first order sine wave.The experimental platform of water-entry supercavitating projectile was established,and the experimental data are compared with the calculated data to verify the effectiveness of the numerical method.（2）Investigation of water-entry cavity flow and motion characteristics of supercavitating projectile in hydrostatic environment.Based on ANSYS FLUENT,the water-entry process of supercavitating projectile under different water entry velocity,attack angle and angle was calculated.The numerical calculation results such as water density distribution cloud diagram,velocity streamline diagram and hydrodynamic characteristic curve of supercavitating projectile were obtained,and the influence of cavity flow and motion characteristics of supercavitating projectile in hydrostatic environment is analyzed.（3）Investigation multiphase coupling mechanical characteristics of supercavitating projectile in wave environment.Numerical simulations were carried out under different water-entry velocities and attack angles in wave environment,and the situation of supercavitating projectile entering and leaving water for many times in wave environment was studied.The influence mechanism of wave environment on the water-entry cavity flow and motion characteristics of supercavitating projectile was revealed by analyzing the calculation results of water density distribution cloud diagram,velocity streamline diagram and hydrodynamic characteristic curve between wave environment and hydrostatic environment.A certain theoretical basis can be provide for improving the effective range and firing accuracy of amphibious firearms,which have important practical application value.