Mechanics2DRigidOscillPart.cpp

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/*--------------------------------*- VM2D -*-----------------*---------------*\
| ##  ## ##   ##  ####  #####   |                            | Version 1.14   |
| ##  ## ### ### ##  ## ##  ##  |  VM2D: Vortex Method       | 2026/03/06     |
| ##  ## ## # ##    ##  ##  ##  |  for 2D Flow Simulation    *----------------*
|  ####  ##   ##   ##   ##  ##  |  Open Source Code                           |
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| Copyright (C) 2017-2026 I. Marchevsky, K. Sokol, E. Ryatina, A. Kolganova   |
*-----------------------------------------------------------------------------*
| File name: Mechanics2DRigidOscillPart.cpp                                   |
| Info: Source code of VM2D                                                   |
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\*---------------------------------------------------------------------------*/
 
 
#include "Mechanics2DRigidOscillPart.h"
 
#include "Airfoil2D.h"
#include "Boundary2D.h"
#include "MeasureVP2D.h"
#include "StreamParser.h"
#include "Velocity2D.h"
#include "Wake2D.h"
#include "World2D.h"
 
using namespace VM2D;
 
MechanicsRigidOscillPart::MechanicsRigidOscillPart(const World2D& W_, size_t numberInPassport_)
    :
    Mechanics(W_, numberInPassport_, true, false)
    //, V0({ 0.0, 0.0 })
    //, r0({ W_.getAirfoil(numberInPassport_).rcm[0], W_.getAirfoil(numberInPassport_).rcm[1] })
{
    Vcm0 = { 0.0, 0.0 };
    Rcm0 = { W_.getAirfoil(numberInPassport_).rcm[0], W_.getAirfoil(numberInPassport_).rcm[1] };
    Vcm = Vcm0;
    Rcm = Rcm0;
    VcmOld = Vcm0;
    RcmOld = Rcm;
 
    strongCoupling = false;
        
    ReadSpecificParametersFromDictionary();
    Initialize(initVelocity, W_.getAirfoil(numberInPassport_).rcm + initDisplacement, initAngularVelocity, W_.getAirfoil(numberInPassport_).phiAfl + initAngularDisplacement);
};
 
//Вычисление гидродинамической силы, действующей на профиль
void MechanicsRigidOscillPart::GetHydroDynamForce()
{
    W.getTimers().start("Force");
 
    const double& dt = W.getPassport().timeDiscretizationProperties.dt;
 
    hydroDynamForce = { 0.0, 0.0 };
    hydroDynamMoment = 0.0;
 
    viscousForce = { 0.0, 0.0 };
    viscousMoment = 0.0;
 
    Point2D hDFGam = { 0.0, 0.0 };      //гидродинамические силы, обусловленные присоед.завихренностью
    Point2D hDFdelta = { 0.0, 0.0 };    //гидродинамические силы, обусловленные приростом завихренности
    Point2D hDFQ = { 0.0, 0.0 };        //гидродинамические силы, обусловленные присоед.источниками
 
    double hDMGam = 0.0;                //гидродинамический момент, обусловленный присоед.завихренностью
    double hDMdelta = 0.0;              //гидродинамический момент, обусловленный приростом завихренности
    double hDMQ = 0.0;                  //гидродинамический момент, обусловленный присоед.источниками
    for (size_t i = 0; i < afl.getNumberOfPanels(); ++i)
    {
        Point2D rK = 0.5 * (afl.getR(i + 1) + afl.getR(i)) - afl.rcm;
 
        Point2D velK = 0.5 * (afl.getV(i) + afl.getV(i + 1));
        double gAtt = (velK & afl.tau[i]);
 
        double gAttOld = 0.0;
        if (W.getCurrentStep() > 0)
        {
            auto oldAfl = W.getOldAirfoil(numberInPassport);
            gAttOld = ((0.5 * (oldAfl.getV(i) + oldAfl.getV(i + 1))) & oldAfl.tau[i]);
        }
 
        double deltaGAtt = gAtt - gAttOld;
 
        double qAtt = (velK & afl.nrm[i]);
 
        double deltaK = boundary.sheets.freeVortexSheet(i, 0) * afl.len[i] - afl.gammaThrough[i] + deltaGAtt * afl.len[i];
 
        /*1*/
        hDFdelta += deltaK * Point2D({ -rK[1], rK[0] });
        hDMdelta += 0.5 * deltaK * rK.length2();
 
        /*2*/
        hDFGam += 0.5 * velK.kcross() * gAtt * afl.len[i];
        hDMGam += 0.5 * (rK ^ velK.kcross()) * gAtt * afl.len[i];
 
        /*3*/
        hDFQ -= 0.5 * velK * qAtt * afl.len[i];
        hDMQ -= 0.5 * (rK ^ velK) * qAtt * afl.len[i];
    }
 
    const double rho = W.getPassport().physicalProperties.rho;
 
    hydroDynamForce = rho * (hDFGam + hDFdelta * (1.0 / dt) + hDFQ);
    hydroDynamMoment = rho * (hDMGam + hDMdelta / dt + hDMQ);
 
    if ((W.getPassport().physicalProperties.nu > 0.0)/* && (W.currentStep > 0)*/)
        for (size_t i = 0; i < afl.getNumberOfPanels(); ++i)
        {
            Point2D rK = 0.5 * (afl.getR(i + 1) + afl.getR(i)) - afl.rcm;
            viscousForce += rho * afl.viscousStress[i] * afl.tau[i];
            viscousMoment += rho * (afl.viscousStress[i] * afl.tau[i]) & rK;
        }
 
    W.getTimers().stop("Force");
}// GetHydroDynamForce()
 
// Вычисление скорости центра масс
Point2D MechanicsRigidOscillPart::VeloOfAirfoilRcm(double currTime)
{
    return Vcm;
}//VeloOfAirfoilRcm(...)
 
// Вычисление положения центра масс
Point2D MechanicsRigidOscillPart::PositionOfAirfoilRcm(double currTime)
{
    return Rcm;
}//PositionOfAirfoilRcm(...)
 
double MechanicsRigidOscillPart::AngularVelocityOfAirfoil(double currTime)
{
    return Wcm;
}//AngularVelocityOfAirfoil(...)
 
double MechanicsRigidOscillPart::AngleOfAirfoil(double currTime)
{
    if (afl.phiAfl != Phi)
    {
        std::cout << "afl.phiAfl != Phi" << std::endl;
        exit(100600);
    }
 
    return afl.phiAfl;
}//AngleOfAirfoil(...)
 
// Вычисление скоростей начал панелей
void MechanicsRigidOscillPart::VeloOfAirfoilPanels(double currTime)
{
    Point2D veloRcm = VeloOfAirfoilRcm(currTime);
 
    std::vector<Point2D> veloW(afl.getNumberOfPanels());
    for (size_t i = 0; i < afl.getNumberOfPanels(); ++i)
        veloW[i] = veloRcm + Wcm * (afl.getR(i) - Rcm).kcross();
 
    afl.setV(veloW);
 
    circulationOld = circulation;
    circulation = 2.0 * afl.area * Wcm;
 
}//VeloOfAirfoilPanels(...)
 
 
void MechanicsRigidOscillPart::Move()
{
    Point2D meff;
    //if (W.getPassport().airfoilParams[numberInPassport].addedMass.length2() > 0)
    //  meff = Point2D{ m + W.getPassport().airfoilParams[numberInPassport].addedMass[0], m + W.getPassport().airfoilParams[numberInPassport].addedMass[1] };
    //else
        meff = Point2D{ m, m };
 
        double Jeff = J;
 
    VcmOld = Vcm;
    RcmOld = Rcm;
    PhiOld = Phi;
    WcmOld = Wcm;   
 
    Point2D dr, dV;
    double dphi, dw;
 
    //W.getInfo('t') << "k = " << k << std::endl;
 
    if (k[0] > 0)
    {
        double dt = W.getPassport().timeDiscretizationProperties.dt;
        Point2D kk[4];
 
        kk[0] = { Vcm[0], (hydroDynamForce[0] - 2.0 * b[0] * Vcm[0] - k[0] * Rcm[0]) / meff[0] };
        kk[1] = { Vcm[0] + 0.5 * dt * kk[0][1], (hydroDynamForce[0] - 2.0 * b[0] * (Vcm[0] + 0.5 * dt * kk[0][1]) - k[0] * (Rcm[0] + 0.5 * dt * kk[0][0])) / meff[0] };
        kk[2] = { Vcm[0] + 0.5 * dt * kk[1][1], (hydroDynamForce[0] - 2.0 * b[0] * (Vcm[0] + 0.5 * dt * kk[1][1]) - k[0] * (Rcm[0] + 0.5 * dt * kk[1][0])) / meff[0] };
        kk[3] = { Vcm[0] + dt * kk[2][1], (hydroDynamForce[0] - 2.0 * b[0] * (Vcm[0] + dt * kk[2][1]) - k[0] * (Rcm[0] + dt * kk[2][0])) / meff[0] };
 
        dr[0] = dt * (kk[0][0] + 2. * kk[1][0] + 2. * kk[2][0] + kk[3][0]) / 6.0;
        dV[0] = dt * (kk[0][1] + 2. * kk[1][1] + 2. * kk[2][1] + kk[3][1]) / 6.0;
    }
    else
    {
        dr[0] = 0.0;
        dV[0] = 0.0;
    }
 
 
 
    if (k[1] > 0)
    {
        double dt = W.getPassport().timeDiscretizationProperties.dt;
        Point2D kk[4];
        kk[0] = { Vcm[1], (hydroDynamForce[1] - 2.0 * b[1] * Vcm[1] - k[1] * Rcm[1]) / meff[1]};
        kk[1] = { Vcm[1] + 0.5 * dt * kk[0][1], (hydroDynamForce[1] - 2.0 * b[1] * (Vcm[1] + 0.5 * dt * kk[0][1]) - k[1] * (Rcm[1] + 0.5 * dt * kk[0][0])) / meff[1]};
        kk[2] = { Vcm[1] + 0.5 * dt * kk[1][1], (hydroDynamForce[1] - 2.0 * b[1] * (Vcm[1] + 0.5 * dt * kk[1][1]) - k[1] * (Rcm[1] + 0.5 * dt * kk[1][0])) / meff[1]};
        kk[3] = { Vcm[1] + dt * kk[2][1], (hydroDynamForce[1] - 2.0 * b[1] * (Vcm[1] + dt * kk[2][1]) - k[1] * (Rcm[1] + dt * kk[2][0])) / meff[1]};
                
        dr[1] = dt * (kk[0][0] + 2. * kk[1][0] + 2. * kk[2][0] + kk[3][0]) / 6.0;
        dV[1] = dt * (kk[0][1] + 2. * kk[1][1] + 2. * kk[2][1] + kk[3][1]) / 6.0;
    }
    else
    {
        dr[1] = 0.0;
        dV[1] = 0.0;
    }
 
 
 
    if (kw > 0)
    {
        double dt = W.getPassport().timeDiscretizationProperties.dt;
        Point2D kk[4];
 
        kk[0] = { Wcm, (hydroDynamMoment - 2.0 * bw * Wcm - kw * Phi) / Jeff };
        kk[1] = { Wcm + 0.5 * dt * kk[0][1], (hydroDynamMoment - 2.0 * bw * (Wcm + 0.5 * dt * kk[0][1]) - kw * (Phi + 0.5 * dt * kk[0][0])) / Jeff };
        kk[2] = { Wcm + 0.5 * dt * kk[1][1], (hydroDynamMoment - 2.0 * bw * (Wcm + 0.5 * dt * kk[1][1]) - kw * (Phi + 0.5 * dt * kk[1][0])) / Jeff };
        kk[3] = { Wcm + dt * kk[2][1], (hydroDynamMoment - 2.0 * bw * (Wcm + dt * kk[2][1]) - kw * (Phi + dt * kk[2][0])) / Jeff };
 
        dphi = dt * (kk[0][0] + 2. * kk[1][0] + 2. * kk[2][0] + kk[3][0]) / 6.0;
        dw = dt * (kk[0][1] + 2. * kk[1][1] + 2. * kk[2][1] + kk[3][1]) / 6.0;
    }
    else
    {
        dphi = 0.0;
        dw = 0.0;
    }
 
    afl.Move(dr);
    afl.Rotate(dphi);
 
    Rcm += dr;
    Vcm += dV;
 
    Phi += dphi;
    Wcm += dw;
}//Move()
 
 
 
void MechanicsRigidOscillPart::MoveKinematic()
{
    VcmOld = Vcm;
    RcmOld = Rcm;
 
    Point2D dr, dV;
    double dt = W.getPassport().timeDiscretizationProperties.dt;
 
    if (k[1] > 0)
    {           
        dr[1] = Vcm[1] * dt;
        dV[1] = 0.0;
    }
    else
    {
        dr[1] = 0.0;
        dV[1] = 0.0;
    }
 
 
    if (k[0] > 0)
    {       
        dr[0] = Vcm[0] * dt;
        dV[0] = 0.0;
    }
    else
    {
        dr[0] = 0.0;
        dV[0] = 0.0;
    }
 
    afl.Move(dr);   
            
    Rcm += dr;
    Vcm += dV;
}//MoveKinematic()
 
 
void MechanicsRigidOscillPart::MoveOnlyVelo()
{
    Point2D meff;
    if (W.getPassport().airfoilParams[numberInPassport].addedMass.length2() > 0)
        meff = Point2D{ m + W.getPassport().airfoilParams[numberInPassport].addedMass[0], m + W.getPassport().airfoilParams[numberInPassport].addedMass[1] };
    else
        meff = Point2D{ m, m };
 
    Point2D dr, dV; 
 
    if (k[1] > 0)
    {
        double dt = W.getPassport().timeDiscretizationProperties.dt;
        Point2D kk[4];
    
        kk[0] = { Vcm[1], (hydroDynamForce[1] - 2.0 * b[1] * Vcm[1] - k[1] * Rcm[1]) / meff[1]};
        kk[1] = { Vcm[1] + 0.5 * dt * kk[0][1], (hydroDynamForce[1] - 2.0 * b[1] * (Vcm[1] + 0.5 * dt * kk[0][1]) - k[1] * (Rcm[1] + 0.5 * dt * kk[0][0])) / meff[1]};
        kk[2] = { Vcm[1] + 0.5 * dt * kk[1][1], (hydroDynamForce[1] - 2.0 * b[1] * (Vcm[1] + 0.5 * dt * kk[1][1]) - k[1] * (Rcm[1] + 0.5 * dt * kk[1][0])) / meff[1]};
        kk[3] = { Vcm[1] + dt * kk[2][1], (hydroDynamForce[1] - 2.0 * b[1] * (Vcm[1] + dt * kk[2][1]) - k[1] * (Rcm[1] + dt * kk[2][0])) / meff[1]};
 
        dr[1] = 0.0;// dt* (kk[0][0] + 2.0 * kk[1][0] + 2.0 * kk[2][0] + kk[3][0]) / 6.0;
        dV[1] = dt * (kk[0][1] + 2.0 * kk[1][1] + 2.0 * kk[2][1] + kk[3][1]) / 6.0;
    }
    else
    {
        dr[1] = 0.0;
        dV[1] = 0.0;
    }
 
 
    if (k[0] > 0)
    {
        double dt = W.getPassport().timeDiscretizationProperties.dt;
        Point2D kk[4];
        
        kk[0] = { Vcm[0], (hydroDynamForce[0] - 2.0 * b[0] * Vcm[0] - k[0] * Rcm[0]) / meff[0]};
        kk[1] = { Vcm[0] + 0.5 * dt * kk[0][1], (hydroDynamForce[0] - 2.0 * b[0] * (Vcm[0] + 0.5 * dt * kk[0][1]) - k[0] * (Rcm[0] + 0.5 * dt * kk[0][0])) / meff[0]};
        kk[2] = { Vcm[0] + 0.5 * dt * kk[1][1], (hydroDynamForce[0] - 2.0 * b[0] * (Vcm[0] + 0.5 * dt * kk[1][1]) - k[0] * (Rcm[0] + 0.5 * dt * kk[1][0])) / meff[0]};
        kk[3] = { Vcm[0] + dt * kk[2][1], (hydroDynamForce[0] - 2.0 * b[0] * (Vcm[0] + dt * kk[2][1]) - k[0] * (Rcm[0] + dt * kk[2][0])) / meff[0]};
 
        dr[0] = 0.0; // dt* (kk[0][0] + 2.0 * kk[1][0] + 2.0 * kk[2][0] + kk[3][0]) / 6.0;
        dV[0] = dt * (kk[0][1] + 2.0 * kk[1][1] + 2.0 * kk[2][1] + kk[3][1]) / 6.0;
    }
    else
    {
        dr[0] = 0.0;
        dV[0] = 0.0;
    }
 
    //afl.Move({ dx, dy });
    Vcm += dV;  
    
}//MoveOnlyVelo()
 
 
 
#if defined(INITIAL) || defined(BRIDGE) 
void MechanicsRigidOscillPart::ReadSpecificParametersFromDictionary()
{
    /*
    mechParamsParser->get("m", m);  
    W.getInfo('i') << "mass " << "m = " << m << std::endl;
 
    mechParamsParser->get("J", J);
    W.getInfo('i') << "moment of inertia " << "J = " << J << std::endl;
 
    
    mechParamsParser->get("k", k);
    mechParamsParser->get("kw", kw);
 
    W.getInfo('i') << "linear rigidity (kx, ky) = " << k << std::endl;  
    W.getInfo('i') << "rotational rigidity kw = " << kw << std::endl;   
 
    Point2D c;
    mechParamsParser->get("c", c);//Логарифмический декремент
    double cw;
    mechParamsParser->get("cw", cw);//Логарифмический декремент
 
    b[0] = c[0] / 2.0;
    b[1] = c[1] / 2.0;
    bw = cw / 2.0;
 
    W.getInfo('i') << "linear damping (bx, by) = " << b << std::endl;
    W.getInfo('i') << "rotational damping bw = " << bw << std::endl;
 
    mechParamsParser->get("initDisplacement", initDisplacement, &defaults::defaultInitDisplacement);
    mechParamsParser->get("initAngularDisplacement", initAngularDisplacement, &defaults::defaultInitAngularDisplacement);
    W.getInfo('i') << "initial displacement: " << "translational = " << initDisplacement << ", rotational = " << initAngularDisplacement << std::endl;
 
    mechParamsParser->get("initVelocity", initVelocity, &defaults::defaultInitVelocity);
    mechParamsParser->get("initAngularVelocity", initAngularVelocity, &defaults::defaultInitAngularVelocity);
    W.getInfo('i') << "initial velocity: " << "translational = " << initVelocity << ", rotational = " << initAngularVelocity << std::endl;
 
    //*/
 
    //*
    mechParamsParser->get("m", m);  
    W.getInfo('i') << "mass " << "m = " << m << std::endl;
 
    mechParamsParser->get("J", J);
    W.getInfo('i') << "moment of inertia " << "J = " << J << std::endl;
        
    Point2D sh;
    mechParamsParser->get("sh", sh);    
    k[0] = m * sqr(2.0 * PI * sh[0] / W.getPassport().airfoilParams[numberInPassport].chord) * W.getPassport().physicalProperties.vInf.length2();
    k[1] = m * sqr(2.0 * PI * sh[1] / W.getPassport().airfoilParams[numberInPassport].chord) * W.getPassport().physicalProperties.vInf.length2();
    
    double shw;
    mechParamsParser->get("shw", shw);
    kw = J * sqr(2.0 * PI * shw / W.getPassport().airfoilParams[numberInPassport].chord) * W.getPassport().physicalProperties.vInf.length2();
    
    W.getInfo('i') << "linear rigidity (kx, ky) = " << k << std::endl;  
    W.getInfo('i') << "rotational rigidity kw = " << kw << std::endl;   
 
    Point2D zeta;
    mechParamsParser->get("zeta", zeta);//Логарифмический декремент
    double zetaw;
    mechParamsParser->get("zetaw", zetaw);//Логарифмический декремент
 
    b[0] = zeta[0] / (2.0 * PI) * sqrt(k[0] * m);
    b[1] = zeta[1] / (2.0 * PI) * sqrt(k[1] * m);
    bw = zetaw / (2.0 * PI) * sqrt(kw * J);
 
    W.getInfo('i') << "linear damping (bx, by) = " << b << std::endl;
    W.getInfo('i') << "rotational damping bw = " << bw << std::endl;
 
 
    mechParamsParser->get("initDisplacement", initDisplacement, &defaults::defaultInitDisplacement);
    mechParamsParser->get("initAngularDisplacement", initAngularDisplacement, &defaults::defaultInitAngularDisplacement);
    W.getInfo('i') << "initial displacement: " << "translational = " << initDisplacement << ", rotational = " << initAngularDisplacement << std::endl;
 
    mechParamsParser->get("initVelocity", initVelocity, &defaults::defaultInitVelocity);
    mechParamsParser->get("initAngularVelocity", initAngularVelocity, &defaults::defaultInitAngularVelocity);
    W.getInfo('i') << "initial velocity: " << "translational = " << initVelocity << ", rotational = " << initAngularVelocity << std::endl;
    //*/
 
}//ReadSpecificParametersFromDictionary()
#endif