From e45871398244bf9495b21372f71bca99a0d74f9d Mon Sep 17 00:00:00 2001 From: Guillaume Giudicelli Date: Mon, 10 Nov 2025 13:17:01 -0700 Subject: [PATCH 1/2] Add a dedicated linear WCNSFV page with links to the relevant sections in linearFV, NS and physics refs #31887 --- .../finite_volumes/linear_fv_design.md | 1 - .../content/modules/navier_stokes/index.md | 16 +++-- .../modules/navier_stokes/linear_wcnsfv.md | 67 +++++++++++++++++++ 3 files changed, 76 insertions(+), 8 deletions(-) create mode 100644 modules/navier_stokes/doc/content/modules/navier_stokes/linear_wcnsfv.md diff --git a/framework/doc/content/finite_volumes/linear_fv_design.md b/framework/doc/content/finite_volumes/linear_fv_design.md index 7837beda70cd..57384151209a 100644 --- a/framework/doc/content/finite_volumes/linear_fv_design.md +++ b/framework/doc/content/finite_volumes/linear_fv_design.md @@ -1,4 +1,3 @@ - # Linear Finite Volume Design Decisions in MOOSE The main motivation for introducing a new approach for finite volume system diff --git a/modules/navier_stokes/doc/content/modules/navier_stokes/index.md b/modules/navier_stokes/doc/content/modules/navier_stokes/index.md index 7116d047ec7d..cc7ffbe7a4c5 100644 --- a/modules/navier_stokes/doc/content/modules/navier_stokes/index.md +++ b/modules/navier_stokes/doc/content/modules/navier_stokes/index.md @@ -3,16 +3,15 @@ The MOOSE Navier-Stokes module is a library for the implementation of simulation tools that solve the Navier-Stokes equations using either the continuous Galerkin finite element (CGFE) or finite volume (FV) methods. The Navier-Stokes -equations are usually solved using either the pressure-based, incompressible formulation (assuming a -constant fluid density), or a density-based, compressible formulation, although -there are plans to add a finite volume weakly-compressible pressured-based implementation in -the not-too-distant future. +equations are usually solved using either the pressure-based, incompressible or weakly-compressible formulation (assuming a +constant or pressure-independent fluid density), or a density-based, compressible formulation. For documentation specific to finite element or finite volume implementations, please refer to the below pages: - [Incompressible Finite Volume](insfv.md) - [Weakly Compressible Finite Volume](wcnsfv.md) +- [Weakly compressible finite volume using a linear discretization and a segregated solvealgorithm (SIMPLE/PIMPLE)](linear_wcnsfv.md) - [Porous media Incompressible Finite Volume](pinsfv.md) - [Continuous Galerkin Finite Element](navier_stokes/cgfe.md) - [Hybridized Discontinous Galerkin (HDG) Finite Element](NavierStokesLHDGKernel.md) @@ -25,7 +24,7 @@ please refer to the below pages: Here we give a brief tabular summary of the Navier-Stokes implementations: !table id=navier_stokes_summary caption=Summary of Navier-Stokes implementations -| prefix | Jacobian | compressibility | turbulence support | friction support | method | advection strategy | +| prefix | Jacobian | compressibility | turbulence support | friction support | discretiz. | advection strategy | | ------ | -------- | ----------------------------- | --------------------------- | ---------------- | ------ | --------------------------------- | | INS | Hand-coded | incompressible | None | Not porous | CGFE | SUPG | | INSAD | AD | incompressible | Smagorinsky | Not porous | CGFE | SUPG | @@ -35,7 +34,9 @@ Here we give a brief tabular summary of the Navier-Stokes implementations: | INSChorin | Hand-coded | incompressible | None | Not porous | CGFE | Chorin predictor-corrector | | INSFV | AD | incompressible | mixing length; $k-\epsilon$ | Not porous | FV | RC, CD velocity; limited advected | | WCNSFV | AD | weakly compressible | mixing length | Not porous | FV | RC, CD velocity; limited advected | +| Linear(WCNS)FV | N/A | weakly compressible | $k-\epsilon$ | Not porous | LinearFV | RC velocity; limited advected | | WCNSFV2P | AD | weakly compressible; 2-phase | mixing length | Not porous | FV | RC, CD velocity; limited advected | +| LinearWCNSFV2P | N/A | weakly compressible; 2-phase | None | Not porous | LinearFV | RC velocity; limited advected | | PINSFV | AD | incompressible | mixing length | Darcy, Forcheimer | FV | RC, CD velocity; limited advected | | CNSFVHLLC | AD | compressible | None | Not porous | FV | HLLC, piecewise constant data | | PCNSFVHLLC | AD | compressible | None | Darcy, Forcheimer | FV | HLLC, piecewise constant data | @@ -49,6 +50,7 @@ Table definitions: - WCNS2P: weakly-compressible Navier-Stokes 2-phase - CNS: compressible Navier-Stokes - PINS or PCNS: porous incompressible Navier-Stokes or porous compressible Navier-Stokes +- LinearFV: the [linear finite volume discretization](linear_fv_design.md) - SUPG: Streamline-Upwind Petrov-Galerkin - RC: Rhie-Chow interpolation - CD: central differencing interpolation; equivalent to average interpolation @@ -78,7 +80,7 @@ As Navier-Stokes Finite Volume solvers continue to evolve in MOOSE, many new sol | Turbulence | Mixing length | Yes | Yes | Yes | | | | $k-\epsilon$ | | Yes | Yes | Yes | | | $k-\omega$ SST | | | in [PR #28151](https://github.com/idaholab/moose/pull/28151) | | -| Two-phase | Mixture model | Yes | Yes | Yes | in [PR #29614](https://github.com/idaholab/moose/pull/29614) | +| Two-phase | Mixture model | Yes | Yes | Yes | Yes | | | Eulerian-Eulerian | | | Yes | | | Porous Flow | -- | Yes | Yes | Yes | | | Compressibility | Incompressible | Yes | Yes | Yes | Yes | @@ -91,7 +93,7 @@ As Navier-Stokes Finite Volume solvers continue to evolve in MOOSE, many new sol | Physics Syntax | Flow | | Yes | | Yes | | | Fluid heat transfer | | Yes | | Yes | | | Solid phase heat transfer | | Yes | | | -| | Two phase | | Yes | | in [PR #29614](https://github.com/idaholab/moose/pull/29614) | +| | Two phase | | Yes | | Yes | | | Turbulence | | Yes | | | | | Scalar transport | | Yes | | Yes | diff --git a/modules/navier_stokes/doc/content/modules/navier_stokes/linear_wcnsfv.md b/modules/navier_stokes/doc/content/modules/navier_stokes/linear_wcnsfv.md new file mode 100644 index 000000000000..7333d2b2e342 --- /dev/null +++ b/modules/navier_stokes/doc/content/modules/navier_stokes/linear_wcnsfv.md @@ -0,0 +1,67 @@ +# Weakly Compressible Navier Stokes using the Linear Finite Volume discretization + +## Equations + +The linear finite volume discretization of the weakly compressible Navier Stokes equations is used +to solve the following equations: + +- conservation of momentum +- pressure-correction (see [SIMPLE.md]) +- turbulence equations +- conservation of energy +- conservation of advected passive scalars +- conservation of an advected phase in a homogeneous mixture + +We refer the reader to the respective `Physics` pages, listed in [linear_wcnsfv.md#syntax], for the strong form of the equations. + +## Solver algorithm(s) + +For steady state simulations, you may use the [SIMPLE.md] executioner which implements the SIMPLE algorithm [!citep](patankar1983calculation). + +For transient simulations, you may use the [PIMPLE.md] executioner which implements the PIMPLE algorithm [!citep](greenshieldsweller2022). + +## Discretization + +### General + +We use the linear finite volume discretization, a face-centered finite volume discretization. We have implemented orthogonal +gradient correction and skewness correction for face values, and thus can reach second-order accuracy in many cases. + +!alert note +Triangular and tetrahedral meshes currently only achieve first order convergence rates at the moment. + +!alert note +This implementation does not require forming a Jacobian because it is solving using the SIMPLE/PIMPLE algorithm, which +involve segregated linear equation solved nested in a fixed point iteration loop, rather than a Newton method-based solver. +The discretization of the equation is optimized to form a right hand side (RHS) and sparse matrices. +Additional details about the linear finite volume discretization can be found on [this page](linear_fv_design.md). + +### Advection term + +The advection term is discretized using the Rhie Chow interpolation for the face velocities. Additional details may be found in the documentation +for the object handling the computation of the Rhie Chow velocities: the [RhieChowMassFlux.md]. + +## Syntax id=syntax + +These equations can be created in MOOSE using the [LinearFVKernels](syntax/LinearFVKernels/index.md) and [LinearFVBCs](syntax/LinearFVBCs/index.md) +classes, or using the [Physics](syntax/Physics/index.md) classes. +For `LinearWCNSFV`, the relevant `Physics` classes are: + +- [WCNSLinearFVFlowPhysics.md] for the velocity-pressure coupling. +- [WCNSLinearFVFluidHeatTransferPhysics.md] for the fluid energy conservation equation. +- [WCNSLinearFVScalarTransportPhysics.md] for the advection of passive scalars. + +For `LinearWCNSFV2P`, the relevant `Physics` classes are: + +- [WCNSLinearFVTwoPhaseMixturePhysics.md] for a basic implementation of a mixture model. + +## Validation + +The linear finite volume discretization is being verified and validated as part of the `OpenPronghorn` open-source software. +Please refer to [OpenPronghorn](https://mooseframework.inl.gov/open_pronghorn/) for this ongoing effort. + +## Gallery + +!alert construction +The gallery has not been created for this discretization yet. +Please refer to [OpenPronghorn](https://mooseframework.inl.gov/open_pronghorn/) for example simulations. From 7da9e88bab8525d2ca366459bc2ebbb251ad2f54 Mon Sep 17 00:00:00 2001 From: Guillaume Giudicelli Date: Tue, 11 Nov 2025 16:15:03 -0700 Subject: [PATCH 2/2] Address Alex's review - accept all suggestions on wording and precisions Co-authored-by: Alex Lindsay --- .../content/modules/navier_stokes/index.md | 6 ++--- .../modules/navier_stokes/linear_wcnsfv.md | 24 +++++++++---------- 2 files changed, 15 insertions(+), 15 deletions(-) diff --git a/modules/navier_stokes/doc/content/modules/navier_stokes/index.md b/modules/navier_stokes/doc/content/modules/navier_stokes/index.md index cc7ffbe7a4c5..0d2c86c52bd0 100644 --- a/modules/navier_stokes/doc/content/modules/navier_stokes/index.md +++ b/modules/navier_stokes/doc/content/modules/navier_stokes/index.md @@ -10,8 +10,8 @@ For documentation specific to finite element or finite volume implementations, please refer to the below pages: - [Incompressible Finite Volume](insfv.md) -- [Weakly Compressible Finite Volume](wcnsfv.md) -- [Weakly compressible finite volume using a linear discretization and a segregated solvealgorithm (SIMPLE/PIMPLE)](linear_wcnsfv.md) +- [Weakly Compressible Finite Volume using nonlinear systems and most often a monolithic Newton solve algorithm](wcnsfv.md) +- [Weakly compressible finite volume using linear systems and a segregated solve algorithm (SIMPLE/PIMPLE)](linear_wcnsfv.md) - [Porous media Incompressible Finite Volume](pinsfv.md) - [Continuous Galerkin Finite Element](navier_stokes/cgfe.md) - [Hybridized Discontinous Galerkin (HDG) Finite Element](NavierStokesLHDGKernel.md) @@ -50,7 +50,7 @@ Table definitions: - WCNS2P: weakly-compressible Navier-Stokes 2-phase - CNS: compressible Navier-Stokes - PINS or PCNS: porous incompressible Navier-Stokes or porous compressible Navier-Stokes -- LinearFV: the [linear finite volume discretization](linear_fv_design.md) +- LinearFV: the [linear system based finite volume discretization](linear_fv_design.md) - SUPG: Streamline-Upwind Petrov-Galerkin - RC: Rhie-Chow interpolation - CD: central differencing interpolation; equivalent to average interpolation diff --git a/modules/navier_stokes/doc/content/modules/navier_stokes/linear_wcnsfv.md b/modules/navier_stokes/doc/content/modules/navier_stokes/linear_wcnsfv.md index 7333d2b2e342..4bb5a0fb01bc 100644 --- a/modules/navier_stokes/doc/content/modules/navier_stokes/linear_wcnsfv.md +++ b/modules/navier_stokes/doc/content/modules/navier_stokes/linear_wcnsfv.md @@ -1,8 +1,8 @@ -# Weakly Compressible Navier Stokes using the Linear Finite Volume discretization +# Weakly Compressible Navier Stokes using a Linear Finite Volume Implementation ## Equations -The linear finite volume discretization of the weakly compressible Navier Stokes equations is used +The linear finite volume implementation of the weakly compressible Navier Stokes equations is used to solve the following equations: - conservation of momentum @@ -18,27 +18,27 @@ We refer the reader to the respective `Physics` pages, listed in [linear_wcnsfv. For steady state simulations, you may use the [SIMPLE.md] executioner which implements the SIMPLE algorithm [!citep](patankar1983calculation). -For transient simulations, you may use the [PIMPLE.md] executioner which implements the PIMPLE algorithm [!citep](greenshieldsweller2022). +For transient simulations, you may use the [PIMPLE.md] executioner which implements the PIMPLE algorithm [!citep](greenshieldsweller2022), which is a blend of PISO inner iterations and SIMPLE outer iterations. ## Discretization ### General -We use the linear finite volume discretization, a face-centered finite volume discretization. We have implemented orthogonal -gradient correction and skewness correction for face values, and thus can reach second-order accuracy in many cases. +We use a linearized cell-centered finite volume discretization. We have implemented orthogonal +gradient correction and skewness correction for face values and gradients, and thus can reach second-order accuracy in many cases. !alert note -Triangular and tetrahedral meshes currently only achieve first order convergence rates at the moment. +Triangular and tetrahedral meshes currently only achieve first order spatial convergence rates at the moment. !alert note -This implementation does not require forming a Jacobian because it is solving using the SIMPLE/PIMPLE algorithm, which -involve segregated linear equation solved nested in a fixed point iteration loop, rather than a Newton method-based solver. -The discretization of the equation is optimized to form a right hand side (RHS) and sparse matrices. +This implementation does not form a Jacobian because it uses the SIMPLE/PIMPLE algorithm, which +solves segregated linear equations nested within a kind of fixed point iteration loop, rather than Newton. +Instead of forming a residual and Jacobian, this implementation forms a right hand side (RHS) and sparse coefficient matrix for direct use within linear system solvers. Additional details about the linear finite volume discretization can be found on [this page](linear_fv_design.md). ### Advection term -The advection term is discretized using the Rhie Chow interpolation for the face velocities. Additional details may be found in the documentation +The advection term uses the Rhie Chow interpolation for computation of face velocities. Additional details may be found in the documentation for the object handling the computation of the Rhie Chow velocities: the [RhieChowMassFlux.md]. ## Syntax id=syntax @@ -57,11 +57,11 @@ For `LinearWCNSFV2P`, the relevant `Physics` classes are: ## Validation -The linear finite volume discretization is being verified and validated as part of the `OpenPronghorn` open-source software. +The linear finite volume implementation is being verified and validated as part of the `OpenPronghorn` open-source software. Please refer to [OpenPronghorn](https://mooseframework.inl.gov/open_pronghorn/) for this ongoing effort. ## Gallery !alert construction -The gallery has not been created for this discretization yet. +The gallery has not been created for this finite volume implementation yet. Please refer to [OpenPronghorn](https://mooseframework.inl.gov/open_pronghorn/) for example simulations.