A multiphase SPH framework for supercooled large droplets dynamics

Abstract

Purpose This paper aims to introduce a three-dimensional smoothed particle hydrodynamics (SPH) framework for simulating supercooled large droplets (SLD) dynamics at aeronautical speeds. Design/methodology/approach To include the effects of the surrounding air, a multiphase model capable of handling high density-ratio problems is adopted. A diffusive term is incorporated to smooth the density field and avoid numerical instabilities. Additionally, a particle shifting technique is used to eliminate anisotropic particle distributions. Findings The framework is validated against low-speed droplet impingement experimental results and then applied to the droplet impingement at high speeds typical of SLD conditions. Preliminary parametric studies are conducted to investigate the post-impact splashing. It is observed that a thicker water film can decrease the crown diameter and a smaller impact angle can suppress upward and forward splashing. Originality/value A three-dimensional multiphase SPH framework for SLD dynamics at a wide range of impact speed is developed and validated. The effects of particle resolution, water film thickness and impact angle on the post-impact crown evolution are investigated.

Efficient modeling of liquid splashing via graph neural networks with adaptive filter and aggregator fusion

“…Conventional techniques for liquid splashing simulation, such as the Eulerian MLFLIP and SPH (Jetly and Ibayashi, 2022), while capable of capturing complex liquid behaviors, are hindered by intense computational overhead, impeding real-time deployment (Macklin et al , 2014; Dibaji et al , 2021). Advancements in modeling splashing directly using graph convolutions have demonstrated the potential to accelerate simulations (Cui et al , 2019; Ray et al , 2013). However, improving generalizability and stability remains an open challenge (Ernez and Morency, 2019).…”

“…For instance, the density of a particle i is computed as the sum of the masses of neighboring particles within the kernel's radius of influence, weighted by W ( r , h ) (Müller et al , 2003; Cui et al , 2019): …”

Sustainable future for icing tankers in civil aviation certification

“…FAA [15] provides airplane and engine certification requirements in supercooled large drop. Kong W [16], Cutting D [17], Cui X [18], Yu C [19] research and discus the theory for the freezing transition of supercooled large water droplet.…”

Numerical simulation of drop deformation under simple shear flow of Giesekus fluids by SPH

“…Both fluids are considered to be weakly compressible in this study so that the pressure can be related to the density through an appropriate equation of state such as (Monaghan, 1994;Cui et al, 2019;Rahmat et al, 2020a):…”

“…Both fluids are considered to be weakly compressible in this study so that the pressure can be related to the density through an appropriate equation of state such as (Monaghan, 1994; Cui et al , 2019; Rahmat et al , 2020a): where c 0 , ρ 0 , γ and p 0 are sound speed, initial density, polytropic constant and backpressure, respectively. The numerical sound speed is chosen at least ten times larger than the maximum velocity encountered in the domain to limit the density variations lower than 0.01 (Lio and Lio, 2003).…”