Fluid Mechanics#

This page presents the fluid mechanics analyses currently supported by OpenPisco and their corresponding mathematical formulations.

Overview#

At present, OpenPisco provides support for incompressible steady-state laminar fluid flow simulations through an interface with OpenFOAM.

Supported Analyses#

  • Incompressible steady-state laminar flow

Incompressible Steady-State Laminar Flow#

The flow is governed by the incompressible Navier-Stokes equations

\[\begin{split}\begin{equation} \label{eq:steady_state_NS_incompressible} \left\{ \begin{array}{rllll} \text{div}(v) &=& 0 & \text{in} & \Omega_f,\\ -\text{div}(\sigma_f(v,p)) + \rho \nabla v\,v &=& f_f & \text{in} & \Omega_f,\\ v &=& v_0 & \text{on} & \partial\Omega^D_f,\\ \sigma_f(v,p)n &=& 0 & \text{on} & \partial\Omega^N_f,\\ v &=& 0 & \text{on} & \Gamma. \end{array} \right. \end{equation}\end{split}\]

where:

  • \(\rho\) is the fluid density;

  • \(v\) is the velocity field;

  • \(p\) is the pressure field;

  • \(f_f\) is the density of volumic forces acting on \(\Omega_f\);

  • \(\sigma_f\) is the stress tensor of a Newtonian fluid.

The fluid stress tensor is defined as

\[\begin{equation} \sigma_f(v,p)=2\mu e(v)-pI, \end{equation}\]

where

\[e(v)=\frac{\nabla v + (\nabla v)^T}{2}\]

is the strain-rate tensor and \(\mu\) denotes the dynamic viscosity.

Associated Implementation#

The current implementation is provided through: