OpenFOAM再发新版！知识根本学不完

前几天ESI那面发布新版OpenFOAM-v2406，这最近OpenFOAM基金会发布OpenFOAM-12。岳子这一只把OpenFOAM当做CFD实战教材来学习CFD算法。这新知识根本学不完啊！

不过岳子的虚拟机已经包含了。大家想用直接下载就行。

新版的特点直接给你们发英文原文。这玩意翻译成中文吧，如果不懂背后的算法，翻译的没那个味道。索性不翻译了，我知道关注咱这个号的英语六级都是600多分。

Modular Solvers

• General: The re-reading of input parameters by solver modules is simpler and more efficient [ commit 6054b1 ]. Multi-region cases now include simpler controls to stop a solution when it reaches a particular tolerance [ commit 815f0b ].

• Incompressible and compressible solvers: The dnsFoam solver is replaced by the incompressibleFluid solver module with the OUForce fvModel [ commit cf0610 ].

• Solid solvers: Corrected the solid solver module by moving the thermophysical model corrector step inside the non-orthogonal corrector loop [ commit 3c347ca5 ].

• Film solvers: The impingement pressure is corrected in the isothermalFilm solver module [ commit 0b321e ].

• Numerics: Created a new sourceProxy() function for source terms for one variable which are applied to an equation for a different variable, e.g. volume/mass sources applied to a pressure equation (rather than density) [ commit a5ea0b ].

Multiphase

• Momentum transfer: multiphaseEulerFoam includes a new implicit drag algorithm which significantly improves convergence for small particle and Euler-VoF high-drag cases [ commit 5fd304 ]. New implicit virtual-mass force implementation which significantly improves convergence for bubbly-flow cases [ commit 18200e ].

• Mass transfer: multiphaseEulerFoam now includes homogeneous condensation and phase separation models [ commit 046680c4 ]. The coefficientMassTransfer fvModel is a prototype example that generates mass transfer between two phases [ commit 2f018f ].

• Heat transfer: Added a simple Prandtl heat transfer model to the multiphaseEuler solver, which creates a heat transfer coefficient in proportion with the corresponding drag model’s momentum transfer coefficient [ commit 01d0af39  ].

• Solid phases:  Added a new thermal phase model for solid phases [ commit 020463 ]. Improved support for stationary phases [ commits 9c3a40 ]. Updated to use the new phaseSolidThermophysicalTransportModel class, supporting anisotropic conduction in stationary solid phases [ commit 5e0387 ]. New IsothermalSolidPhaseModel for isothermal stationary solid phases [ commit ad3d25 ].

• Boundary conditions: The multiphaseExternalTemperature boundary condition provides a version of externalTemperature for the multiphaseFluid solver module [ commit 6fce00 ].

• Interface capturing: In multiphase solvers, made the compressive interface schemes, e.g. PLIC, MPLIC, more robust with the Crank-Nicolson time scheme [ commit 7ec1e2 ].

• Surface waves: New irregular surface wave models [ commit c0da2a ]. The GodaJONSWAP wave spectrum provides an alternative, approximate parameterisation of the JONSWAP spectrum, in which the significant wave height and period are specified instead of the wind speed and fetch [ commit cbec0045 ].

Turbulence Modelling

• RAS modelling: The lower limit in the bounding of turbulent dissipation epsilon is now based on a maximum turbulent viscosity nut rather than a minimum epsilon value which improves stability and robustness [ commit 854f4541 ] ; also the same for turbulent dissipation omega  [ commit 195dfbe1 ]. 

• Wall functions: The alphatJayatillekeWallFunction thermal wall function uses yPlus from the respective nut momentum wall function to simplify the implementation and provide greater consistency [ commit 054a5206 ]. Reimplemented the corner weighting for omega and epsilon in turbulence wall functions  [ commit 1218bd08 ].  Corrected mapping of wall function boundary conditions for non-conformal multi-regions cases [ commit b6caf356 ].

Heat

• Energy: New viscousHeating fvModel add the viscous heating source to the total energy equation [ commit bbc39318 ].

• Thermodynamics: All property functions in thermodynamics are now consistent with energies and enthalpies using lower case character to denote that they are specific quantities [ commit abe43a95 ].

Particles and Tracking

• Distributions: Generalised the code for distributions so they can be used more widely, including in the rewriting particle code [ commit e1e0e258 ].

• Injection: In Lagrangian modelling, the U0 entry in the patch injection model can now specify a field name from which the initial velocity will be interpolated [ commit 96b61305 ].

• Data processing: New volumeFraction function calculates the volume fraction of a particle cloud [ commit 31b096 ].

Meshes

• General: The dynamicMesh library has been separated into the polyTopoChange and motionSolvers libraries following a major refactoring of code to improve maintainability [ commit b9fe7df3 ].

• Generation: New cylindricalRadial extrusion method added to extrudeMesh [ commit e880ec ]. extrudeMesh can now allocate newly generated cells to one or more cellZones [ commit 33aa4496 ]. snappyHexMesh can now generate region meshes directly into a regions subdirectories using the -region option [ commit 9ace5366 ]. Corrected the use of the featureAngle parameter for layer insertion in snappyHexMesh [ commit 47fa9bc6 ].

• Multiple regions: mergeMeshes can combine a list of separate meshes (separate polyMesh directories) into a single mesh (one polyMesh directory) [ commit f47e1b0b ]. Replaced the stitchMesh application to use the patch intersection functionality from the non-conformal coupled interface [ commit 69da8f3d ]

• Non-Conformal Coupling: Making NCC compatible with mesh motion with parallel redistribution (load-balancing) and adaptive refinement [ commit 9af6bd ]. Improved robustness of the mesh stitcher, e.g. for NCC [ commit 2057174b ].

• Boundary: New patchOrder utility allows users to reorder the patches of a mesh [ commit 4707bc91 ].

• Other: Meshes can be checked with the checkMesh utility or checkMesh function object (the latter for moving mesh cases), which now have consistent controls and code [ commit 4ab997 ]. checkMesh includes a stopAt option which causes the code to solver if any mesh quality check fails (typically in a moving mesh case)  [ commit 06ecc011 ].

• Motion: New fvMeshMover for multi-valve IC engine mesh motion [ commit 7d65e66b ].

• Zones: Improved mesh zone handling [ commit ca2cae8c ] including reducing code duplication [ commit 4ad52ea1 ]

Parallel Running

• Load-balancing: Particle cloud tracking and/or chemistry integration can use automatic load-balancing during a parallel simulation by switching on CPU load caching [ commit 41705e9e ].  The new parMETIS interface provided load-balancing with multi-constraints and redistribution using the ParMETIS distributor [ commit 40bcabf7 ].  The aachenBomb tutorial example demonstrates multi-constraint load-balancing with both Lagrangian and chemistry [ commit e727809b ].

• Decomposition and redistribution: decomposePar now correctly creates nonConformalProcessorCyclic patches when using NCC [ commit 89c818 ]. Improved parallel robustness of dynamic mesh refinement [ commit cd133a28 ].  Zoltan can now be used for mesh redistribution when some processors temporarily contain zero cells, which can occur especially when meshing in parallel with snappyHexMesh [ commit adfc80c4 ]; same for ParMETIS  [ commit 3cdec1dc ].

Function Objects

• General: Function objects should be configured in a separate system/functions file, to avoid unnecessary reading and building of function objects when they are not required [ commit de363dde ]. New fluidMaxDelta function object can set the maximum time step and Courant number as a function of time [ commit 277944 ]. The writeObjects functionObject prints all the object names and their types from the object registry when the specified object is not found [ commit 5039aec6 ]. Function objects which operate on patches can read both the patch keyword for a single patch and patches for multiple patches [ commit e5f48bfc ]. 

• Forces: New movingForces and rigidBodyForces function objects calculate and write the forces and moments on moving rigid bodies with specified or calculated centre of rotation [ commit 2daceb90 ]. The wallShearStress function object calculates on any type of wall patch, e.g. filmWall [ commit 898cb9b5 ].

• Fields: The cylindrical packaged function object transforms a vector field into cylindrical co-ordinates [ commit 1622e190 ]. New specieFlux, specieAdvectiveFlux and specieDiffusiveFlux function objects calculate the fluxes of fluid species as a surfaceScalarField [ commit dab3104d ].

• IC Engines: The new multiValveEngineState functionObject prints and logs piston and valve motion in IC engine calculations [ commit 9753b67f ].

• Other: In the phaseScalarTransport function object, if the alphaPhi field is not present, it can be calculated by setting a new solveAlphaPhi switch [ commit 2bc91ecf ]

Models

• General: MRF can work with adaptive mesh refinement [ commit cdef2003 ].

• Fluid sources: The new volumeSource fvModel applies a volume source to the continuity equation for incompressible solvers, and an equivalent massSource fvModel for compressible solvers [ commit 9181a6 ].  Sources from fvModels, which introduce fluid to the domain, are now specified in the boundaryField section of field files [ commit 171101 ].

• Momentum: New propellerDisk fvModel provides a disk momentum source which approximates a propeller, based on a propeller curve [ commit b3b1b5b6 ]

• Other: A new OUForce fvModel calculates and applies a random Ornstein-Uhlenbeck process force to the momentum equation for direct numerical simulation of boxes of isotropic turbulence [ commit f0ee70 ].

General Boundary Conditions

• Pressure: The entrainmentPressure boundary condition is recommended for pressure at open boundaries in the template case examples [ commit 2a9a2d0e ].

• Velocity: The angular velocity can now be specified in rad/s or rpm in the cylindricalInletVelocity boundary condition, which describes an inlet velocity in cylindrical co-ordinates [ commit 755a3d ]. The movingMappedWallVelocity boundary condition can be used at an interface between two mesh regions to apply a no-slip condition from a wall on one side, to the fluid on the other [ commit 59ebac71 ].

• Temperature: New lumpedMassTemperature boundary condition models temperature of a solid body bounded wholly or partially by the boundary patch [ commit 3ab0e63e ].

• General: For a Function1 with table data, the interpolation scheme defaults to linear, but can now be set to step [ commit 50c053 ]. Simplified field mapping across all boundary conditions [ commit cef86f ]. The polynomial Function1 has a simpler input syntax [ commit c3f131e8 ].

• Coupled: The nonConformalMappedWall patch type provides a flexible way of connecting meshes from separate regions, e.g. for CHT, without the need for faces to conform at the interface [ commit a3e38977 ].

Case Configuration

• Data Visualisation: foamMonitor has new options to select columns of data, plot the independent variable on y-axis, and to display a single graph without refreshing periodically [ commit 9252d0c0 ].

• Case Initialisation: deltaTFactor can be set in the controlDict file to limit the rate of adjustment in a variable time step, defaults to 1.2 [ commit 9aaf94 ]. Dimensionless parameters can be specified by dimensions []; [ commit 87ff44 ].  foamDictionary now includes an -output option to write a modified dictionary to any specified file [ commit 6d9bc6 ].  dimensioned parameters can now be specified with dimensions before or after the values [ commit 209a3756 ]. foamDictionary now includes an option to rename entries in input files [ commit b0dbdd4a ].

• Units: Units, e.g. [bar] for pressure, can now be specified for input parameters, which are converted to conventional units, e.g. kg/(ms²) [ commit 476bb42b ]. New foamUnits script describes units (e.g. [cal], [J]) and their conversions, and dimensional units, for input parameters [ commit e4abe3d5 ].  Units can be included with input parameters that use tabulated data, e.g. for rotational speed omega specified as [rpm] [ commit 3928fbb8 ].