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December 20, 2016 / by Ram / In SPH / Comments

SPH Advantages

Features

  • The most popular and widely used among them.
  • Has been applied to various fluid flows involving diverse physical phenomena, from astrophysical to non-Newtonian fluid flows, but also to structure deformation and fracturing.
  • Expanding very quickly among the academia and the industry.
  • To be compared to the traditional numerical methods in CFD – typically, finite-difference/finite-element/finite-volume methods combined with volume-of-fluid/level-set methods -, which rely on a Eulerian, mesh-based approach.
  • Much more recent research area (e.g., first application to free-surface flows in 1994) , but already starting to outperform the traditional methods on certain kinds of scenarios.

What are the main advantages?

  • No advection term to model.
  • No need for generating or adapting a mesh.
  • No need for a tracking interface method, such as volume-of-fluid/level-set methods.

What are the main disadvantages ?

  1. Higher computational cost for approximating the spatial derivatives.
  2. More difficulties for prescribing the boundary conditions.

For what kinds of flows it tends to be preferred?

  1. Violent, convection-dominated dynamics (1).
  2. Large deformation of the fluid domain (2).
  3. Interactions with geometrically complex structures (3).
  4. Interactions with highly deforming/moving structures (4).
  5. Multi-phase processes (e.g., air-water mixtures, sediment flows, granular flows) (5).

Typical Scenarios in the Industry Industry

  • Tsunami wave impact: (1)+(2)+(3)
  • Dam break-induced: (1)+(2)+(3)
  • Internal flooding: (2)+(3)
  • High wind impact: (1)+(3)+(4)
  • Radioactive Particles/Debris Tracking (4)+(5)

Why Neutrino-SPH

  • Ability to handle Implicit-Incompressible and Compressible Flows
  • Could be easily integrated into the Moose framework – Ability to compute on HPC Machines (Falcon and other linux/windows clusters) – Ability to couple other simulations from other 2D/3D domains
  • Coupling with Shallow Water code – Example: GeoClaw/Neutrino Coupling (Dam Breaks simulated) – Example: SWASH/Neutrino Coupling (Lake Break Simulated)
  • Coupling from Varying Scales
  • From Geographic Scales to a localized representation
  • Coupling with Bernoulli’s Model or Torricelli’s Model
  • Ability to model Rain water based inflow
  • Ability to model Pipe flows
  • Coupling with Rigid Body Solvers – Linear and Angular Momentum conservation with accurate Rigid-Fluid Coupling – Example: Bullet-Physics
  • Validated Results (Impact Force) on Rigids – Example: Dam Break Scenario – Flexible Open Boundaries for inflow and outflow conditions – Easy Setup of Periodic Boundaries – Easy Coupling with other PRA Systems (EMRALD) – Tested – Easy setup of Particle Deamons for optimizing computations – Mass conserving Killers/Emitters/Transporters – Has been used in a variety of Industry Level Applications
  • Pipe Breaks
  • Rain induced Flooding
  • Lake Breaches impacting structures
  • Lake Overtopping
  • Tsunami induced flooding
  • Room Level Flooding affecting components and Real-time feedback – Variable resolution to compromise accuracy for speed
  • Almost Real-time feedback/coupling with PRA systems
  • Easy import of geometry from various architectural/engineering formats
  • Easy setup of model for simulation and visualization.
  • Easy setup of initial conditions of Fluids using Volumetric Operations (Booleans)
  • GPGPU Version and Distributed version currently under development.
  • Cross Platform (Windows/Linux)

For what kind of flows the traditional/mesh based methods tend to be preferred?

  • Nearly-steady regime.
  • Turbulent regime in confined domain.
  • Interactions with simple shaped, static rigid structures.