Numerical simulation of water entry problems considering air effect using a multiphase Riemann-SPH model

AbstractThe water entry is a classic fluid-structure interaction problem in ocean engineering. The prediction of impact loads on structure during the water entry is critical to some engineering applications. In this paper, a multiphase Riemann-SPH model is developed to investigate water entry problems. In this model, a special treatment, a cut-off value for the particle density, is arranged to avoid the occurrence of negative pressure. A remarkable advantage of the present multiphase SPH model is that the real speed of sound in air can be allowed when simulating water-air flows. In the present work, considering the air effect, several typical water entry problems are studied, and the evolution of multiphase interface, the motion characteristic of structure and complex fluid-structure interactions during the water entry are analyzed. Compared with the experimental data, the present multiphase SPH model can obtain satisfactory results, and it can be considered as a reliable tool in reproducing some fluid-structure interaction problems.

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On removing the numerical instability induced by negative pressures in SPH simulations of typical fluid–structure interaction problems in ocean engineering

Applied Ocean Research ◽

10.1016/j.apor.2021.102938 ◽

2021 ◽

Vol 117 ◽

pp. 102938

Author(s):

Hong-Guan Lyu ◽

Peng-Nan Sun ◽

Xiao-Ting Huang ◽

Shun-Hua Chen ◽

A-Man Zhang

Keyword(s):

Fluid Structure Interaction ◽

Numerical Instability ◽

Ocean Engineering ◽

Fluid Structure ◽

Structure Interaction ◽

Negative Pressures

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A Hybrid Numerical Model to Address Fluid Elastic Structure Interaction

Volume 7: Ocean Engineering ◽

10.1115/omae2016-54161 ◽

2016 ◽

Author(s):

Manoj Kumar Gangadharan ◽

Sriram Venkatachalam

Keyword(s):

Numerical Model ◽

Fluid Structure Interaction ◽

Breaking Waves ◽

Elastic Structure ◽

Navier Stokes ◽

Breaking Wave ◽

Ocean Engineering ◽

Fluid Structure ◽

Strongly Coupled ◽

Structure Interaction

Hydroelasticity is an important problem in the field of ocean engineering. It can be noted from most of the works published as well as theories proposed earlier that this particular problem was addressed based on the time independent/ frequency domain approach. In this paper, we propose a novel numerical method to address the fluid-structure interaction problem in time domain simulations. The hybrid numerical model proposed earlier for hydro-elasticity (Sriram and Ma, 2012) as well as for breaking waves (Sriram et al 2014) has been extended to study the problem of breaking wave-elastic structure interaction. The method involves strong coupling of Fully Nonlinear Potential Flow Theory (FNPT) and Navier Stokes (NS) equation using a moving overlapping zone in space and Runge kutta 2nd order with a predictor corrector scheme in time. The fluid structure interaction is achieved by a near strongly coupled partitioned procedure. The simulation was performed using Finite Element method (FEM) in the FNPT domain, Particle based method (Improved Meshless Local Petrov Galerkin based on Rankine source, IMPLG_R) in the NS domain and FEM for the structural dynamics part. The advantage of using this approach is due to high computational efficiency. The method has been applied to study the interaction between breaking waves and elastic wall.

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SPH model for fluid–structure interaction and its application to debris flow impact estimation

Landslides ◽

10.1007/s10346-016-0777-4 ◽

2016 ◽

Vol 14 (3) ◽

pp. 917-928 ◽

Cited By ~ 46

Author(s):

Zili Dai ◽

Yu Huang ◽

Hualin Cheng ◽

Qiang Xu

Keyword(s):

Debris Flow ◽

Fluid Structure Interaction ◽

Fluid Structure ◽

Structure Interaction ◽

Sph Model

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Fluid Structure Interaction of Buoyant Bodies with Free Surface Flows: Computational Modelling and Experimental Validation

Water ◽

10.3390/w11051048 ◽

2019 ◽

Vol 11 (5) ◽

pp. 1048 ◽

Cited By ~ 4

Author(s):

Andrea Luigi Facci ◽

Giacomo Falcucci ◽

Antonio Agresta ◽

Chiara Biscarini ◽

Elio Jannelli ◽

...

Keyword(s):

Free Surface ◽

Numerical Model ◽

Fluid Structure Interaction ◽

Free Surface Flow ◽

Surface Flow ◽

Water Impact ◽

Ocean Engineering ◽

Fluid Structure ◽

Structure Interaction ◽

Wide Range

In this paper we present a computational model for the fluid structure interaction of a buoyant rigid body immersed in a free surface flow. The presence of a free surface and its interaction with buoyant bodies make the problem very challenging. In fact, with light (compared to the fluid) or very flexible structures, fluid forces generate large displacements or accelerations of the solid and this enhances the artificial added mass effect. Such a problem is relevant in particular in naval and ocean engineering and for wave energy harvesting, where a correct prediction of the hydrodynamic loading exerted by the fluid on buoyant structures is crucial. To this aim, we develop and validate a tightly coupled algorithm that is able to deal with large structural displacement and impulsive acceleration typical, for instance, of water entry problems. The free surface flow is modeled through the volume of fluid model, the finite volume method is utilized is to discretize the flow and solid motion is described by the Newton-Euler equations. Fluid structure interaction is modeled through a Dirichlet-Newmann partitioned approach and tight coupling is achieved by utilizing a fixed-point iterative procedure. As most experimental data available in literature are limited to the first instants after the water impact, for larger hydrodynamic forces, we specifically designed a set of dedicated experiments on the water impact of a buoyant cylinder, to validate the proposed methodology in a more general framework. Finally, to demonstrate that the proposed numerical model could be used for a wide range of engineering problems related to FSI in multiphase flows, we tested the proposed numerical model for the simulation of a floating body.

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