From 94d3e79a8617f88dc0219cfdeedfa3147833719d Mon Sep 17 00:00:00 2001 From: Adrian Kummerlaender Date: Mon, 24 Jun 2019 14:43:36 +0200 Subject: Initialize at openlb-1-3 --- .../youngLaplace3d/youngLaplace3d.cpp | 316 +++++++++++++++++++++ 1 file changed, 316 insertions(+) create mode 100644 examples/multiComponent/youngLaplace3d/youngLaplace3d.cpp (limited to 'examples/multiComponent/youngLaplace3d/youngLaplace3d.cpp') diff --git a/examples/multiComponent/youngLaplace3d/youngLaplace3d.cpp b/examples/multiComponent/youngLaplace3d/youngLaplace3d.cpp new file mode 100644 index 0000000..c18cf5a --- /dev/null +++ b/examples/multiComponent/youngLaplace3d/youngLaplace3d.cpp @@ -0,0 +1,316 @@ +/* Lattice Boltzmann sample, written in C++, using the OpenLB + * library + * + * Copyright (C) 2018 Robin Trunk + * E-mail contact: info@openlb.net + * The most recent release of OpenLB can be downloaded at + * + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the Free + * Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + * Boston, MA 02110-1301, USA. + */ + +/* youngLaplace3d.cpp + * In this example a Young-Laplace test is performed. A spherical domain + * of fluid 2 is immersed in fluid 1. A diffusive interface forms and the + * surface tension can be calculated using the Laplace pressure relation. + * The pressure difference is calculated between a point in the middle of + * the circular domain and a point furthest away from it in the + * computational domain (here left bottom corner). + * + * This example shows the simplest case for the free-energy model with two + * fluid components. + */ + +#include "olb3D.h" +#include "olb3D.hh" // use only generic version! +#include +#include +#include + +using namespace olb; +using namespace olb::descriptors; +using namespace olb::graphics; +using namespace std; + +typedef double T; +#define DESCRIPTOR D3Q19 + +// Parameters for the simulation setup +const int N = 100; +const T nx = 100.; +const T radius = 0.25 * nx; +const T alpha = 1.5; // Interfacial width [lattice units] +const T kappa1 = 0.0075; // For surface tensions [lattice units] +const T kappa2 = 0.005; // For surface tensions [lattice units] +const T gama = 1.; // For mobility of interface [lattice units] + +const int maxIter = 60000; +const int vtkIter = 200; +const int statIter = 200; + + +void prepareGeometry( SuperGeometry3D& superGeometry ) { + + OstreamManager clout( std::cout,"prepareGeometry" ); + clout << "Prepare Geometry ..." << std::endl; + + superGeometry.rename( 0,1 ); + + superGeometry.innerClean(); + superGeometry.checkForErrors(); + superGeometry.print(); + + clout << "Prepare Geometry ... OK" << std::endl; +} + + +void prepareLattice( SuperLattice3D& sLattice1, + SuperLattice3D& sLattice2, + Dynamics& bulkDynamics1, + Dynamics& bulkDynamics2, + UnitConverter& converter, + SuperGeometry3D& superGeometry ) { + + OstreamManager clout( std::cout,"prepareLattice" ); + clout << "Prepare Lattice ..." << std::endl; + + // define lattice Dynamics + sLattice1.defineDynamics( superGeometry, 0, &instances::getNoDynamics() ); + sLattice2.defineDynamics( superGeometry, 0, &instances::getNoDynamics() ); + + sLattice1.defineDynamics( superGeometry, 1, &bulkDynamics1 ); + sLattice2.defineDynamics( superGeometry, 1, &bulkDynamics2 ); + + // bulk initial conditions + // define spherical domain for fluid 2 + std::vector v( 3,T() ); + AnalyticalConst3D zeroVelocity( v ); + + AnalyticalConst3D one ( 1. ); + SmoothIndicatorSphere3D sphere( {nx/2., nx/2., nx/2.}, radius, 10.*alpha ); + + AnalyticalIdentity3D rho( one ); + AnalyticalIdentity3D phi( one - sphere - sphere ); + + sLattice1.iniEquilibrium( superGeometry, 1, rho, zeroVelocity ); + sLattice2.iniEquilibrium( superGeometry, 1, phi, zeroVelocity ); + + sLattice1.initialize(); + sLattice2.initialize(); + + clout << "Prepare Lattice ... OK" << std::endl; +} + + +void prepareCoupling(SuperLattice3D& sLattice1, + SuperLattice3D& sLattice2) { + + OstreamManager clout( std::cout,"prepareCoupling" ); + clout << "Add lattice coupling" << endl; + + // Add the lattice couplings + // The chemical potential coupling must come before the force coupling + FreeEnergyChemicalPotentialGenerator3D coupling1( + alpha, kappa1, kappa2); + FreeEnergyForceGenerator3D coupling2; + + sLattice1.addLatticeCoupling( coupling1, sLattice2 ); + sLattice2.addLatticeCoupling( coupling2, sLattice1 ); + + clout << "Add lattice coupling ... OK!" << endl; +} + + +void getResults( SuperLattice3D& sLattice2, + SuperLattice3D& sLattice1, int iT, + SuperGeometry3D& superGeometry, Timer& timer, + UnitConverter converter) { + + OstreamManager clout( std::cout,"getResults" ); + SuperVTMwriter3D vtmWriter( "youngLaplace3d" ); + + if ( iT==0 ) { + // Writes the geometry, cuboid no. and rank no. as vti file for visualization + SuperLatticeGeometry3D geometry( sLattice1, superGeometry ); + SuperLatticeCuboid3D cuboid( sLattice1 ); + SuperLatticeRank3D rank( sLattice1 ); + vtmWriter.write( geometry ); + vtmWriter.write( cuboid ); + vtmWriter.write( rank ); + vtmWriter.createMasterFile(); + } + + // Get statistics + if ( iT%statIter==0 ) { + // Timer console output + timer.update( iT ); + timer.printStep(); + sLattice1.getStatistics().print( iT, converter.getPhysTime(iT) ); + sLattice2.getStatistics().print( iT, converter.getPhysTime(iT) ); + } + + // Writes the VTK files + if ( iT%vtkIter==0 ) { + AnalyticalConst3D half_( 0.5 ); + SuperLatticeFfromAnalyticalF3D half(half_, sLattice1); + + SuperLatticeDensity3D density1( sLattice1 ); + density1.getName() = "rho"; + SuperLatticeDensity3D density2( sLattice2 ); + density2.getName() = "phi"; + + SuperIdentity3D c1 (half*(density1+density2)); + c1.getName() = "density-fluid-1"; + SuperIdentity3D c2 (half*(density1-density2)); + c2.getName() = "density-fluid-2"; + + vtmWriter.addFunctor( density1 ); + vtmWriter.addFunctor( density2 ); + vtmWriter.addFunctor( c1 ); + vtmWriter.addFunctor( c2 ); + vtmWriter.write( iT ); + + // calculate bulk pressure, pressure difference and surface tension + if(iT%statIter==0) { + AnalyticalConst3D two_( 2. ); + AnalyticalConst3D onefive_( 1.5 ); + AnalyticalConst3D k1_( kappa1 ); + AnalyticalConst3D k2_( kappa2 ); + AnalyticalConst3D cs2_( 1./descriptors::invCs2() ); + SuperLatticeFfromAnalyticalF3D two(two_, sLattice1); + SuperLatticeFfromAnalyticalF3D onefive(onefive_, sLattice1); + SuperLatticeFfromAnalyticalF3D k1(k1_, sLattice1); + SuperLatticeFfromAnalyticalF3D k2(k2_, sLattice1); + SuperLatticeFfromAnalyticalF3D cs2(cs2_, sLattice1); + + // Calculation of bulk pressure: + // c_1 = density of fluid 1; c_2 = density of fluid 2 + // p_bulk = rho*c_s^2 + kappa1 * (3/2*c_1^4 - 2*c_1^3 + 0.5*c_1^2) + // + kappa2 * (3/2*c_2^4 - 2*c_2^3 + 0.5*c_2^2) + SuperIdentity3D bulkPressure ( density1*cs2 + + k1*( onefive*c1*c1*c1*c1 - two*c1*c1*c1 + half*c1*c1 ) + + k2*( onefive*c2*c2*c2*c2 - two*c2*c2*c2 + half*c2*c2 ) ); + + AnalyticalFfromSuperF3D interpolPressure( bulkPressure, true, 1); + double position[3] = { 0.5*nx, 0.5*nx, 0.5*nx }; + double pressureIn = 0.; + double pressureOut = 0.; + interpolPressure(&pressureIn, position); + position[0] = ((double)N/100.)*converter.getPhysDeltaX(); + position[1] = ((double)N/100.)*converter.getPhysDeltaX(); + position[2] = ((double)N/100.)*converter.getPhysDeltaX(); + interpolPressure(&pressureOut, position); + + clout << "Pressure Difference: " << pressureIn-pressureOut << " ; "; + clout << "Surface Tension: " << radius*(pressureIn-pressureOut)/2 << std::endl; + clout << "Analytical Pressure Difference: " << alpha/(3.*radius) * (kappa1 + kappa2) << " ; "; + clout << "Analytical Surface Tension: " << alpha/6. * (kappa1 + kappa2) << std::endl; + } + } +} + + +int main( int argc, char *argv[] ) { + + // === 1st Step: Initialization === + + olbInit( &argc, &argv ); + singleton::directories().setOutputDir( "./tmp/" ); + OstreamManager clout( std::cout,"main" ); + + UnitConverterFromResolutionAndRelaxationTime converter( + (T) N, // resolution + (T) 1., // lattice relaxation time (tau) + (T) nx, // charPhysLength: reference length of simulation geometry + (T) 1.e-6, // charPhysVelocity: maximal/highest expected velocity during simulation in __m / s__ + (T) 0.1, // physViscosity: physical kinematic viscosity in __m^2 / s__ + (T) 1. // physDensity: physical density in __kg / m^3__ + ); + + // Prints the converter log as console output + converter.print(); + + // === 2nd Step: Prepare Geometry === + std::vector extend = { nx, nx, nx }; + std::vector origin = { 0, 0, 0 }; + IndicatorCuboid3D cuboid(extend,origin); +#ifdef PARALLEL_MODE_MPI + CuboidGeometry3D cGeometry( cuboid, converter.getPhysDeltaX(), singleton::mpi().getSize() ); +#else + CuboidGeometry3D cGeometry( cuboid, converter.getPhysDeltaX() ); +#endif + + // set periodic boundaries to the domain + cGeometry.setPeriodicity( true, true, true ); + + // Instantiation of loadbalancer + HeuristicLoadBalancer loadBalancer( cGeometry ); + loadBalancer.print(); + + // Instantiation of superGeometry + SuperGeometry3D superGeometry( cGeometry,loadBalancer ); + + prepareGeometry( superGeometry ); + + // === 3rd Step: Prepare Lattice === + SuperLattice3D sLattice1( superGeometry ); + SuperLattice3D sLattice2( superGeometry ); + + ForcedBGKdynamics bulkDynamics1 ( + converter.getLatticeRelaxationFrequency(), + instances::getBulkMomenta() ); + + FreeEnergyBGKdynamics bulkDynamics2 ( + converter.getLatticeRelaxationFrequency(), gama, + instances::getBulkMomenta() ); + + prepareLattice( sLattice1, sLattice2, bulkDynamics1, bulkDynamics2, + converter, superGeometry ); + + prepareCoupling( sLattice1, sLattice2); + + SuperExternal3D sExternal1 (superGeometry, sLattice1, sLattice1.getOverlap() ); + SuperExternal3D sExternal2 (superGeometry, sLattice2, sLattice2.getOverlap() ); + + // === 4th Step: Main Loop with Timer === + int iT = 0; + clout << "starting simulation..." << endl; + Timer timer( maxIter, superGeometry.getStatistics().getNvoxel() ); + timer.start(); + + for ( iT=0; iT<=maxIter; ++iT ) { + // Computation and output of the results + getResults( sLattice2, sLattice1, iT, superGeometry, timer, converter ); + + // Collide and stream execution + sLattice1.collideAndStream(); + sLattice2.collideAndStream(); + + // MPI communication for lattice data + sLattice1.communicate(); + sLattice2.communicate(); + + // Execute coupling between the two lattices + sLattice1.executeCoupling(); + sExternal1.communicate(); + sExternal2.communicate(); + sLattice2.executeCoupling(); + } + + timer.stop(); + timer.printSummary(); + +} -- cgit v1.2.3