static void Main()
{
const int tsteps = 2000; // time steps
const float physlength = 10.0f; // phys length
const int xsteps = 20; // space nodes quantity for BGK
const int nvlc = 60; // velocity nodes quantity for BGK
//--BGK segment
float[,] f = new float[xsteps, nvlc];
const float Kn = 1.0f;
const float vw = 0.2f; // distance between velocities
float totmass = 0f; // total mass
// initial boundary conditions
float u1 = 0.0f;
float T1 = 1.0f;
float rho1 = 1.0f;
float u2 = 0.0f;
float T2 = 1.0f;
float rho2 = 1.0f;
//--BGK boundaries, time = 0;
for (int k = 0; k < nvlc; ++k)
{
//--hybrid
if (k <= (nvlc - 1) / 2)
{
f[xsteps - 1, k] = BGK_1d._n_eq(T2, rho2, u2, vw, nvlc, k);
f[0, k] = 0;
}
else
{
f[xsteps - 1, k] = 0;
f[0, k] = BGK_1d._n_eq(T1, rho1, u1, vw, nvlc, k);
}
}
BGK_1d bgk = new BGK_1d(f, Kn, vw, physlength, tsteps);
bgk.Solve(tsteps);
//--results
float[,] P = bgk.P();
// float[,] Ps = bgk.Ps();
float[,] U = bgk.U();
float[,] T = bgk.Temperatures();
totmass = 0; //--diagnostics of the left BGK area
for (int i = 0; i < xsteps; i++)
{
Console.WriteLine(i / (xsteps - 1.0f) + " " + P[tsteps - 1, i] + " " + U[tsteps - 1, i] + " " + T[tsteps - 1, i] + " " + P[tsteps - 1, i] * U[tsteps - 1, i]);
totmass = totmass + P[tsteps - 1, i];
}
Console.ReadLine();
}
static void Main()
{
const int tsteps = 10000; // time steps
const float physlength = 1.0f; // phys length
const int xsteps = 51; // space nodes quantity for BGK
const int nvlc = 60; // velocity nodes quantity for BGK
//--BGK segment
float[,] f = new float[xsteps, nvlc];
const float Kn = 1.0f;
const float vw = 0.2f; // distance between velocities
float totmass = 0f; // total mass
// initial boundary conditions
float u1 = 0.5f;
float T1 = 0.7f;
float rho1 = 1.0f;
float u2 = -0.3f;
float T2 = 0.7f;
float rho2 = 1.0f;
//--BGK boundaries, time = 0;
for (int k = 0; k < nvlc; ++k)
{
//--hybrid
if (k <= (nvlc - 1) / 2)
{
f[xsteps - 1, k] = BGK_1d._n_eq(T2, rho2, u2, vw, nvlc, k);
f[0, k] = 0;
}
else
{
f[xsteps - 1, k] = 0;
f[0, k] = BGK_1d._n_eq(T1, rho1, u1, vw, nvlc, k);
}
}
BGK_1d bgk = new BGK_1d(f, Kn, vw, physlength, tsteps);
bgk.Solve(tsteps);
//-- half moments computation
float m0, m1, m2;
m0 = m1 = m2 = 0;
int tstep = 10000 - 1;
int xstep = 10;
// этот код отвечает за подсчет моментов при склейке, его стоит проверить
for (int i = nvlc / 2; i < nvlc; ++i)
{
m0 += bgk.F[tstep, xstep, i];
m1 += bgk.F[tstep, xstep, i] * (vw * (i - (nvlc - 1.0f) / 2.0f));
m2 += bgk.F[tstep, xstep, i] * (vw * (i - (nvlc - 1.0f) / 2.0f))
* (vw * (i - (nvlc - 1.0f) / 2.0f));
}
m0 *= vw; m1 *= vw; m2 *= vw;
//--setting LBE condition (flattice[,] = F(flattice, fleft, fright) )
Console.WriteLine("m0=" + m0 + " m1=" + m1 + " m2=" + m2);
m0 = m1 = m2 = 0;
xstep = 40;
// этот код отвечает за подсчет моментов при склейке, его стоит проверить
for (int i = 0; i < nvlc / 2; ++i)
{
m0 += bgk.F[tstep, xstep, i];
m1 += bgk.F[tstep, xstep, i] * (vw * (i - (nvlc - 1.0f) / 2.0f));
m2 += bgk.F[tstep, xstep, i] * (vw * (i - (nvlc - 1.0f) / 2.0f))
* (vw * (i - (nvlc - 1.0f) / 2.0f));
}
m0 *= vw; m1 *= vw; m2 *= vw;
//--setting LBE condition (flattice[,] = F(flattice, fleft, fright) )
Console.WriteLine("m0=" + m0 + " m1=" + m1 + " m2=" + m2);
//--results
float[,] P = bgk.P();
// float[,] Ps = bgk.Ps();
float[,] U = bgk.U();
float[,] T = bgk.Temperatures();
totmass = 0; //--diagnostics of the left BGK area
for (int i = 0; i < xsteps; i++)
{
Console.WriteLine(i / (xsteps - 1.0f) + " " + P[tsteps - 1, i] + " " + U[tsteps - 1, i] + " " + T[tsteps - 1, i] + " " + P[tsteps - 1, i] * U[tsteps - 1, i]);
totmass = totmass + P[tsteps - 1, i];
}
Console.ReadLine();
}
static void Main()
{
const int tsteps = 2000; // time steps
const float physlength = 10.0f; // phys length
const int xsteps = 20; // space nodes quantity for BGK
const int nvlc = 60; // velocity nodes quantity for BGK
//--hybrid Left and Right BGK segments
float[,] fleft = new float[xsteps, nvlc];
float[,] fright = new float[xsteps, nvlc];
const float Kn = 1.0f;
const float vw = 0.02f; // distance between velocities
float totmass = 0f; // total mass
// initial boundary conditions
float u1 = 0.0f;
float T1 = 1.0f;
float rho1 = 1.0f; // нормировка ? / BGK_1d._n_eq_check_dens(T1, u1, vw, nvlc);
float u2 = 0.0f;
float T2 = 1.0f;
float rho2 = 1.0f; //? / BGK_1d._n_eq_check_dens(T2, u2, vw, nvlc);
//--BGK boundaries, time = 0;
for (int k = 0; k < nvlc; ++k)
{
//--hybrid
if (k <= (nvlc - 1) / 2) // условие может быть не актуальным
{
fright[xsteps - 1, k] = BGK_1d._n_eq(T2, rho2, u2, vw, nvlc, k);
// f[0, k] = 0; не актуально
}
else
{
// f[xsteps - 1, k] = 0; не актуально
fleft[0, k] = BGK_1d._n_eq(T1, rho1, u1, vw, nvlc, k);
}
}
const int nlattice = 161; // space nodes quantity for lattice
float[,] flattice = new float[nlattice, 6];
//--hybrid declaration
BGK_1d bgk_left, bgk_right;
D1Q6E lattice;
// stabilising values for lattice
for (int i = 1; i < nlattice - 1; ++i)
{
flattice[i, 0] = D1Q6E._n_eq_k(1.0f, u1, 0);
flattice[i, 1] = D1Q6E._n_eq_k(1.0f, u1, 1);
flattice[i, 2] = D1Q6E._n_eq_k(1.0f, u1, 2);
flattice[i, 3] = D1Q6E._n_eq_k(1.0f, u1, 3);
flattice[i, 4] = D1Q6E._n_eq_k(1.0f, u1, 4);
flattice[i, 5] = D1Q6E._n_eq_k(1.0f, u1, 5);
}
BGK_1d testBGK = new BGK_1d(fleft, Kn, vw, physlength, 1);
int timeindex = (int)(1.0f / testBGK.dtime());
// I recommend to check this value
for (int time = 0; time < tsteps; ++time)
{
// константа 2000 взята наобум, т.к. заранее это значение неизвестно.
bgk_left = new BGK_1d(fleft, Kn, vw, physlength, timeindex + 1);
bgk_right = new BGK_1d(fright, Kn, vw, physlength, timeindex + 1);
//--hybrid, solve BGK for t = 1.0
bgk_left.Solve(timeindex);
bgk_right.Solve(timeindex);
for (int i = 0; i < xsteps; ++i)
{
for (int j = 0; j < nvlc; ++j)
{
fleft[i, j] = bgk_left.F[timeindex, i, j];
fright[i, j] = bgk_right.F[timeindex, i, j];
}
}
float m0, m1, m2;
m0 = m1 = m2 = 0;
// этот код отвечает за подсчет моментов при склейке, его стоит проверить
for (int i = nvlc / 2; i < nvlc; ++i)
{
m0 += fleft[xsteps - 1, i];
m1 += fleft[xsteps - 1, i] * (vw * (i - (nvlc - 1.0f) / 2.0f));
m2 += fleft[xsteps - 1, i] * (vw * (i - (nvlc - 1.0f) / 2.0f))
* (vw * (i - (nvlc - 1.0f) / 2.0f));
}
// m0 *= 1.0f; m1 *= vw; m2 *= vw; проверить
//--setting LBE condition (flattice[,] = F(flattice, fleft, fright) )
flattice[0, 3] = D1Q6E.distr0(m0, m1, m2);
flattice[0, 4] = D1Q6E.distr1(m0, m1, m2);
flattice[0, 5] = D1Q6E.distr2(m0, m1, m2);
m0 = m1 = m2 = 0;
for (int i = 0; i < nvlc / 2; ++i) // проверить !
{
m0 += fright[0, i];
m1 -= fright[0, i] * (vw * (i - (nvlc - 1.0f) / 2.0f));
m2 += fright[0, i] * (vw * (i - (nvlc - 1.0f) / 2.0f))
* (vw * (i - (nvlc - 1.0f) / 2.0f));
}
// m0 *= 1.0; m1 *= vw; m2 *= vw;
flattice[nlattice - 1, 2] = D1Q6E.distr0(m0, m1, m2);
flattice[nlattice - 1, 1] = D1Q6E.distr1(m0, m1, m2);
flattice[nlattice - 1, 0] = D1Q6E.distr2(m0, m1, m2);
lattice = new D1Q6E(flattice, 1.0f);
flattice = lattice.Solve(); // считает единицу во времени
//--левая точка сращивания
m0 = D1Q6E.moment0(flattice[0, 2], flattice[0, 1], flattice[0, 0]);
m1 = -D1Q6E.moment1(flattice[0, 2], flattice[0, 1], flattice[0, 0]);
m2 = D1Q6E.moment2(flattice[0, 2], flattice[0, 1], flattice[0, 0]);
for (int i = 0; i < nvlc / 2; ++i)
{
fleft[xsteps - 1, i] = vw * 1.0f / (float)Math.Sqrt(2.0 * Math.PI * 1.0f)
* (float)Math.Exp(-
((i - (nvlc - 1.0) / 2.0) * vw) *
((i - (nvlc - 1.0) / 2.0) * vw) / (2.0))
* (float)(m0 + m1 * (i - (nvlc - 1.0) / 2.0) * vw +
(m1 - m0) *
(((i - (nvlc - 1.0) / 2.0) * vw) *
((i - (nvlc - 1.0) / 2.0) * vw) - 1.0)
);
}
//--правая точка сращивания
m0 = D1Q6E.moment0(flattice[nlattice - 1, 3], flattice[nlattice - 1, 4], flattice[nlattice - 1, 5]);
m1 = D1Q6E.moment1(flattice[nlattice - 1, 3], flattice[nlattice - 1, 4], flattice[nlattice - 1, 5]);
m2 = D1Q6E.moment2(flattice[nlattice - 1, 3], flattice[nlattice - 1, 4], flattice[nlattice - 1, 5]);
for (int i = nvlc / 2; i < nvlc; ++i)
{
fright[0, i] = vw * 1.0f / (float)Math.Sqrt(2.0 * Math.PI * 1.0f)
* (float)Math.Exp(-
((i - (nvlc - 1.0) / 2.0) * vw) *
((i - (nvlc - 1.0) / 2.0) * vw) / (2.0))
* (float)(m0 + m1 * (i - (nvlc - 1.0) / 2.0) * vw +
(m1 - m0) *
(((i - (nvlc - 1.0) / 2.0) * vw) *
((i - (nvlc - 1.0) / 2.0) * vw) - 1.0)
);
}
}
//--results
bgk_left = new BGK_1d(fleft, Kn, vw, physlength, 1);
bgk_right = new BGK_1d(fright, Kn, vw, physlength, 1);
float[,] P = bgk_left.P();
float[,] U = bgk_left.U();
float[,] T = bgk_left.Temperatures();
totmass = 0; //--diagnostics of the left BGK area
for (int i = 0; i < xsteps; i++)
{
Console.WriteLine(i / (xsteps - 1.0f) + " "
+ P[0, i] + " "
+ U[0, i] + " "
+ T[0, i] + " "
+ P[0, i] * U[0, i]);
totmass = totmass + P[0, i];
}
//--diagnostics lattice
for (int i = 0; i < nlattice; i++)
{
Console.WriteLine(flattice[i, 0] + " " + flattice[i, 1] + " " + flattice[i, 2] +
" " + flattice[i, 3] + " " + flattice[i, 4] + " " + flattice[i, 5] + " x" + i * 0.5);
}
Console.WriteLine("mass=" + totmass);
Console.ReadLine();
}
