DualSPHysics model | CREST project

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Information

C++ and CUDA code (Dual), based on Smoothed Particle Hydrodynamics method

http://www.dual.sphysics.org/

DualSPHysics is based on the Smoothed Particle Hydrodynamics model named SPHysics (www.sphysics.org). The code is developed to study free-surface flow phenomena where Eulerian methods can be difficult to apply, such as waves or impact of dam-breaks on off-shore structures. DualSPHysics is a set of C++, CUDA and Java codes designed to deal with real-life engineering problems.

Developed by: Alex Crespo, Moncho Gomez-Gesteira, Jose Dominguez (UVigo), Ben Rogers (University of Manchester) et al.

Location

Beach, Dike

Variables

velocity
pressure
density
position

Equations

Navier-Stokes
Lagrangian derivative
discrete summation

Fluid mass balance (continuity)
Fluid momentum and energy balance (Navier-Stokes)
Equation of state (Tait’s, weakly compressible)
Viscosity closure (artificial viscosity, laminar)
Turbulence closure (Sub-Particle Scale)
Interpolation procedure (kernel function)
Free surface (intrinsic, no need of tracking)

Boundary conditions

Dynamic boundary conditions (Crespo et al., 2007)
Floating objects (Monaghan et al., 2003)
Periodic open boundaries (Gomez-Gesteira et al., 2012)
Coupling with Discrete Element Method (Canelas et al., 2016)
Multi-phase: Two-phase liquid-sediment implementation in DualSPHysics (Fourtakas and Rogers, 2016)

Data needs

Measured data:

Steering signal (wave generator)
Solid properties (in case of floating objects)

For validation:

Water surface elevation
Wave forces
Profiles of velocity

Model generated data:

Binary format by default (but also ascii, csv, text, vtk)
Single and double precision results

Coordinate system

Grid type

Advantages

No time-consuming mesh generation necessary

Weaknesses

No higher order time schemes available (2nd order has bugs)
Mature but continuously under development, unsuitable for external users (poorly documented)
Boundary conditions are still an open problem with the SPH community
Convergence
Time-consuming but GPU helps a lot!!

Calibration

Parameters

Initial particle interspace
Kernel length
Coefficient of sound
Viscosity
delta-SPH

Procedure

1-2: usually known (depending on the problem)
3-5: start from recommended values, modify if necessary

Validation

Procedure

Comparison of time series

Validation test cases available

Analytical solutions
Wave flume experiments
Wave tank experiments
OWC experiments
Sloshing experiments
Debris flows

Published: wo, 04/03/2019 - 11:03 | Last updated: di, 11/12/2019 - 11:42