Effect of wettability on the water entry of spherical projectiles: Numerical analysis using smoothed particle hydrodynamics

Abstract

The entry of projectiles into water has been of interest to many scientists and engineers, being crucial to a wide range of engineering applications. The water entry problem is a nonlinear and unsteady phenomenon involving complicated multi-phase flow problems and fluid–solid interaction. Many scientists have been studying water entry problems in various conditions through experimental methods and numerical methods. In this paper, three-dimensional numerical simulations of the water entry problem are carried out. The multiphase flow weakly compressible smoothed particle hydrodynamics model is adopted and three-phase interaction is analyzed using pairwise force smoothed particle hydrodynamics. Dynamic boundary condition and rigid body coupling are introduced for interaction between fluid and solid. Spheres with different wetting characteristics entering water at small Reynolds numbers are investigated. Our results show good agreement with the theoretical models from previous studies into the splashing behavior of spheres. The physics of the different splashing behaviors is discussed in detail.

Parallel water entry: Experimental investigations of hydrophobic/hydrophilic spheres

“…[13][14][15][16][17][18][19][20][21] (3) Aerospace and aeronautical engineering: Water entry studies are relevant to seaplane and spacecraft landing, air-to-water weapons, and they offer insight into the behavior of bombs during water impact. [22][23][24][25][26] Phys. Fluids 35, 103301 (2023); doi: 10.1063/5.0167494 35, 103301-1…”

“…These include the material and surface properties of the projectile, the physical properties of the fluid, the angle and rotation rate of the projectiles when they enter the water, the free-water surface deformations due to forced entry and exit of bodies, and even scenarios involving microgravity. [2][3][4]8,12,26,[61][62][63][64][65][66][67] A review of the existing literature highlights that the field of water entry research has primarily concentrated on examining single projectile impacts on the water surface. However, the investigation of parallel (side-by-side) or tandem (consecutive) water entry involving multiple objects remains relatively unexplored.…”