locomotive.cc

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/*
 * Advanced Simulation Library <http://asl.org.il>
 * 
 * Copyright 2015 Avtech Scientific <http://avtechscientific.com>
 *
 *
 * This file is part of Advanced Simulation Library (ASL).
 *
 * ASL is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, version 3 of the License.
 *
 * ASL 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with ASL. If not, see <http://www.gnu.org/licenses/>.
 *
 */
 

 
#include <utilities/aslParametersManager.h>
#include <math/aslTemplates.h>
#include <aslGeomInc.h>
#include <math/aslPositionFunction.h>
#include <aslDataInc.h>
#include <acl/aclGenerators.h>
#include <writers/aslVTKFormatWriters.h>
#include <num/aslLBGK.h>
#include <num/aslLBGKBC.h>
#include <utilities/aslTimer.h>
#include <readers/aslVTKFormatReaders.h>
 
 
// typedef to switch to double precision
//typedef double FlT;
typedef float FlT;
 
using asl::AVec;
using asl::makeAVec;
 
// Generate geometry of the tunnel
asl::SPDistanceFunction generateTunnel(asl::Block & bl)
{
 
  // Set length of the tunnel to the length (X size) of the block
  double l(bl.getBPosition()[0] - bl.position[0] + bl.dx);
  // Set radius of the tunnel to the ca. half of the block's height (Z size)
  double rTunnel((bl.getBPosition()[2] - bl.position[2]) / 2.1);
 
  // Center of the tunnel (described as cylinder cut by a plane)
  asl::AVec<> center(.5 * (bl.getBPosition() + bl.position));
  center[1] = bl.position[1] + .25 * rTunnel;
 
  // Center of the ground plane (that cuts the cylinder) 
  asl::AVec<> centerG(center); 
  centerG[1] = bl.position[1];
 
  /* DF = DistanceFunction (part of the geometrical module of ASL)
   1. Genarate cylinder
   2. Generate ground plane
   3. Conjunction of the cylinder and the plane ('&' - operator)
   4. Space inversion ('-' - operator) */
  auto tunnel(-(generateDFCylinder(rTunnel, makeAVec(l, 0., 0.), center) &
               generateDFPlane(makeAVec(0., -1., 0.), centerG)));
 
  // Normalize DistanceFunction to the range [-1; 1]
  return normalize(tunnel, bl.dx);
}
 
 
int main(int argc, char* argv[])
{
  /* Convenience facility to manage simulation parameters (and also
   hardware parameters defining platform and device for computations)
   through command line and/or parameters file.
   See `locomotive --help` for more information */
  asl::ApplicationParametersManager appParamsManager("locomotive",
                                                     "1.0");
 
  /* Important: declare Parameters only after declaring
   ApplicationParametersManager instance because each Parameter adds itself
   to it automatically!
   0.08 - default value; will be used if nothing else is provided during
   runtime through command line or parameters file.
   "dx" - option key; is used to specify this parameter through command line
   and/or parameters file, like `locomotive --dx 0.05`
   "space step" - option description; is used in the help output:
   `locomotive -h` and as comment on parameters file generation:
   `locomotive -g ./defaultParameters.ini`
   "m" - parameter units; is used to complement the option description mentioned
   above. Might be used for automatic unit conversion in future (to this end
   it is recommended to use the notation of the Boost::Units library). */
  asl::Parameter<FlT> dx(0.08, "dx", "space step", "m");
  asl::Parameter<FlT> dt(1., "dt", "time step", "s");
  asl::Parameter<FlT> nu(.001, "nu", "kinematic viscosity", "m^2/s");
  asl::Parameter<unsigned int> iterations(10001, "iterations", "iterations number");
  asl::Parameter<string> input("input", "path to the geometry input file");
 
  /* Load previously declared Parameters from command line and/or
  parameters file. Use default values if neither is provided. */
  appParamsManager.load(argc, argv);
 
  /* Set the size of the block to 40x10x15 m (in accordance with the
   locomotive size read later on from the input file) */ 
  AVec<int> size(makeAVec(40., 10., 15.) * (1. / dx.v()));
 
  /* Create block and shift it in accordance with the
   position of the locomotive in the input file */
  asl::Block bl(size, dx.v(), makeAVec(-30., 8.58, 1.53));
 
  // Define dimensionless viscosity value
  FlT nuNum(nu.v() * dt.v() / dx.v() / dx.v());
  
  cout << "Data initialization... " << flush;
 
  // Read geometry of the locomotive from the file `locomotive.stl`
  auto locomotive(asl::readSurface(input.v(), bl));
 
  // Create block for further use
  asl::Block block(locomotive->getInternalBlock());
 
  // Generate memory data container for the tunnel
  auto tunnelMap(asl::generateDataContainerACL_SP<FlT>(block, 1, 1u));
  // Place generated geometry of the tunnel into the tunnel data container
  asl::initData(tunnelMap, generateTunnel(block));
 
  // Data container for air friction field
  auto forceField(asl::generateDataContainerACL_SP<FlT>(block, 3, 1u));
  // Initialization
  asl::initData(forceField, makeAVec(0., 0., 0.));
  
  cout << "Finished" << endl;
 
  cout << "Numerics initialization... " << flush;
 
  // NOTE: the problem is considered in the reference frame related to the locomotive
 
  // Generate numerical method for air flow - LBGK (lattice Bhatnagar–Gross–Krook)
  asl::SPLBGK lbgk(new asl::LBGKTurbulence(block, 
                                           acl::generateVEConstant(FlT(nu.v())),  
                                           &asl::d3q15()));
  lbgk->init();
  // Generate an instance for LBGK data initialization
  asl::SPLBGKUtilities lbgkUtil(new asl::LBGKUtilities(lbgk));
  // Initialize the LBGK internal data with the flow velocity of (0.1, 0, 0) in [lattice units]
  lbgkUtil->initF(acl::generateVEConstant(.1, .0, .0));
 
  auto vfTunnel(asl::generatePFConstant(makeAVec(0.1, 0., 0.)));
 
  std::vector<asl::SPNumMethod> bc;
  std::vector<asl::SPNumMethod> bcV;
 
  // Generate boundary conditions for the tunnel geometry. Constant velocity BC
  bc.push_back(generateBCVelocity(lbgk, vfTunnel, tunnelMap));
  // Generate boundary conditions for the tunnel geometry. Constant velocity BC
  // This BC is used for visualization.
  bcV.push_back(generateBCVelocityVel(lbgk, vfTunnel, tunnelMap));
  bcV.push_back(generateBCNoSlipRho(lbgk, tunnelMap));
 
  // Generate boundary conditions for the locomotive geometry. Non-slip BC
  bc.push_back(generateBCNoSlip(lbgk,  locomotive));
  bcV.push_back(generateBCNoSlipVel(lbgk, locomotive));
  bcV.push_back(generateBCNoSlipRho(lbgk, locomotive));
 
  // Generate constant presure BC for in and out planes of the tunnel
  bc.push_back(generateBCConstantPressureVelocity(lbgk, 1.,
                                                  makeAVec(0.1, 0., 0.),
                                                  {asl::X0, asl::XE}));
 
  // Initialization and building of all BC
  initAll(bc);
  initAll(bcV);
 
  // Generate a numerical method for computation of the air force field that acts on the locomotive
  auto computeForce(generateComputeSurfaceForce(lbgk, forceField, locomotive));
  computeForce->init();
  
  cout << "Finished" << endl;
  cout << "Computing..." << endl;
  asl::Timer timer;
 
  // Initialization of the output system
  // Write the output to the directory containing the input parameters file (default "./")
  asl::WriterVTKXML writer(appParamsManager.getDir() + "locomotive");
  writer.addScalars("map", *locomotive);
  writer.addScalars("tunnel", *tunnelMap);
  writer.addScalars("rho", *lbgk->getRho());
  writer.addVector("v", *lbgk->getVelocity());
  writer.addVector("force", *forceField);
 
  // Execute all BC
  executeAll(bc);
  executeAll(bcV);
  computeForce->execute();
 
  // First data output
  writer.write();
 
  timer.start();
  // Iteration loop 
  for (unsigned int i(1); i < iterations.v(); ++i)
  {
    // One iteration (timestep) of bulk numerical procedure
    lbgk->execute();
    // Execution of the BC procedures
    executeAll(bc);
    // Output and analysis scope
    if (!(i%1000))
    {
      cout << i << endl;
      // Execution of the visualization BC procedures
      executeAll(bcV);
      // Computation of the force field
      computeForce->execute();
      // Data writing
      writer.write();
    }
  }
  timer.stop();
  
  cout << "Finished" << endl; 
 
  cout << "Computation statistic:" << endl;
  cout << "Real Time = " << timer.realTime() << "; Processor Time = "
     << timer.processorTime() << "; Processor Load = "
     << timer.processorLoad() * 100 << "%" << endl;
 
  return 0;
}