void initialize(GridNode* g) {
State::turn_fluid_on();
State U = Vector<Real, STATE_NF>(0.0);
Real r, d, r1, d0, alpha;
alpha = 1.0 / 15.0;
d0 = pow(alpha * alpha / POLY_K / 5.0, -3.0);
State::d_floor = d0 / 1.0e+10;
for (int k = 0; k < GNX; k++) {
for (int j = 0; j < GNX; j++) {
for (int i = 0; i < GNX; i++) {
U = Vector<Real, STATE_NF>(0.0);
r = sqrt(g->xc(i) * g->xc(i) + g->yc(j) * g->yc(j) + g->zc(k) * g->zc(k));
r1 = r / alpha;
if (r1 < 3.7) {
d = lane_emden(r1);
U.d() = max(d0 * d, State::d_floor);
} else {
U.d() = State::d_floor;
}
U.tau() = POLY_K * pow(U.d(), State::fgamma) / (State::fgamma - 1.0);
_3Vec X;
X[0] = g->xc(i);
X[1] = g->yc(j);
X[2] = g->xc(k);
U.floor(X);
(*g)(i, j, k) = U;
}
}
}
State::turn_fluid_off();
}
std::vector<real> star(real x, real y, real z) {
x -= x0;
y -= y0_;
z -= z0;
real theta;
const real n = real(1) / (fgamma - real(1));
const real rho_min = 1.0e-3;
std::vector < real > u(NF, real(0));
const real r = std::sqrt(x * x + y * y + z * z) / alpha;
const real theta_min = std::pow(rho_min, real(1) / n);
const auto c0 = real(4) * real(M_PI) * alpha * alpha / (n + real(1));
if (r <= rmax) {
theta = lane_emden(r, dr);
theta = std::max(theta, theta_min);
} else {
theta = theta_min;
}
u[rho_i] = std::pow(theta, n);
u[egas_i] = std::pow(theta, fgamma * n) * c0 / (fgamma - real(1));
//if (theta <= theta_min) {
// u[egas_i] *= real(100);
//}
u[tau_i] = std::pow(u[egas_i], (real(1) / real(fgamma)));
return u;
}
void star_force(real x, real y, real z, real& fx, real& fy, real& fz) {
x -= x0;
y -= y0_;
z -= z0;
constexpr
real mtot = 3.410854709920873e+01;
real m;
const real r = std::sqrt(x * x + y * y + z * z) / alpha;
if (r < rmax) {
lane_emden(r, dr, &m);
} else {
m = mtot;
}
fx = -m * x / (r * r * r);
fy = -m * y / (r * r * r);
fz = -m * z / (r * r * r);
}