static inline v4su sign_test(v4sf n, struct ray ray, float a) { m34sf p = ray_point(n, ray); v4sf v = curve(p, a); m34sf p0 = ray_point(n + v4sf_set1(-0.0001), ray); m34sf p1 = ray_point(n + v4sf_set1(0.0001), ray); v4sf v0 = curve(p0, a); v4sf v1 = curve(p1, a); return sign_change(v, v0) | sign_change(v, v1); }
static inline v4sf bisect(i4sf l, struct ray ray, float a) { i4sf k = l; m34sf p0 = ray_point(k.min, ray); v4sf v0 = curve(p0, a); for (int i = 0; i < 20; i++) { v4sf x = v4sf_set1(0.5) * (k.min + k.max); m34sf p1 = ray_point(x, ray); v4su test = sign_change(v0, curve(p1, a)); k.min = v4sf_select(test, k.min, x); k.max = v4sf_select(test, x, k.max); } return v4sf_set1(0.5) * (k.min + k.max); }
static inline v4sf newton_bisect(i4sf l, struct ray ray, float a) { i4sf k = l; m34sf p0 = ray_point(k.min, ray); v4sf v0 = curve(p0, a); for (int i = 0; i < 20; i++) { v4sf x = v4sf_set1(0.5) * (k.min + k.max); m34sf p1 = ray_point(x, ray); v4sf n = x - curve(p1, a) / m34sf_dot(ray.d, gradient(p1, a)); v4su inside = v4sf_lt(k.min, n) & v4sf_lt(n, k.max); v4sf nx = v4sf_select(inside, n, x); m34sf p2 = ray_point(nx, ray); v4su test = sign_change(v0, curve(p2, a)); k.min = v4sf_select(test, k.min, nx); k.max = v4sf_select(test, nx, k.max); } return v4sf_set1(0.5) * (k.min + k.max); }
static inline v4su localize(i4sf *l, struct ray ray, float a) { float coarse = 0.05; float fine = 0.001; i4sf k = *l; m34sf p0 = ray_point(k.min, ray); v4sf v0 = curve(p0, a); v4su test = v4su_set1(0); while (!v4su_all_ones(test | v4sf_ge(k.min, l->max))) { v4sf x = v0 / m34sf_dot(ray.d, gradient(p0, a)); v4sf step = v4sf_clamp(v4sf_abs(x), v4sf_set1(fine), v4sf_set1(coarse)); k.max = v4sf_select(test, k.max, k.min + step); m34sf p1 = ray_point(k.max, ray); v4sf v1 = curve(p1, a); test |= v4sf_lt(k.max, l->max) & sign_change(v0, v1); k.min = v4sf_select(test, k.min, k.max); v0 = v1; p0 = p1; } l->min = v4sf_select(test, k.min, l->min); l->max = v4sf_select(test, k.max, l->max); return test; }
/* problem: */ void problem(DomainS *pDomain) { GridS *pG = pDomain->Grid; int i,j,k,n,converged; int is,ie,il,iu,js,je,jl,ju,ks,ke,kl,ku; int nx1, nx2, nx3; Real x1, x2, x3; Real a,b,c,d,xmin,xmax,ymin,ymax; Real x,y,xslow,yslow,xfast,yfast; Real R0,R1,R2,rho,Mdot,K,Omega,Pgas,beta,vR,BR,vphi,Bphi; ConsS *Wind=NULL; Real *pU=NULL,*pUl=NULL,*pUr=NULL; Real lsf,rsf; is = pG->is; ie = pG->ie; nx1 = ie-is+1; js = pG->js; je = pG->je; nx2 = je-js+1; ks = pG->ks; ke = pG->ke; nx3 = ke-ks+1; il = is-nghost*(nx1>1); iu = ie+nghost*(nx1>1); nx1 = iu-il+1; jl = js-nghost*(nx2>1); ju = je+nghost*(nx2>1); nx2 = ju-jl+1; kl = ks-nghost*(nx3>1); ku = ke+nghost*(nx3>1); nx3 = ku-kl+1; #ifndef CYLINDRICAL ath_error("[cylwindrotb]: This problem only works in cylindrical!\n"); #endif #ifndef MHD ath_error("[cylwindrotb]: This problem only works in MHD!\n"); #endif if (nx1==1) { ath_error("[cylwindrotb]: Only R can be used in 1D!\n"); } else if (nx2==1 && nx3>1) { ath_error("[cylwindrotb]: Only (R,phi) can be used in 2D!\n"); } /* Allocate memory for wind solution */ if ((Wind = (ConsS*)calloc_1d_array(nx1+1,sizeof(ConsS))) == NULL) ath_error("[cylwindrotb]: Error allocating memory\n"); /* Allocate memory for grid solution */ if ((RootSoln = (ConsS***)calloc_3d_array(nx3,nx2,nx1,sizeof(ConsS))) == NULL) ath_error("[cylwindrotb]: Error allocating memory\n"); theta = par_getd("problem","theta"); omega = par_getd("problem","omega"); vz = par_getd("problem","vz"); /* This numerical solution was obtained from MATLAB. * Ideally, we replace this with a nonlinear solver... */ xslow = 0.5243264128; yslow = 2.4985859152; xfast = 1.6383327831; yfast = 0.5373957134; E = 7.8744739104; eta = 2.3608500383; xmin = par_getd("domain1","x1min")/R_A; xmax = par_getd("domain1","x1max")/R_A; ymin = 0.45/rho_A; ymax = 2.6/rho_A; printf("theta = %f,\t omega = %f,\t eta = %f,\t E = %f\n", theta,omega,eta,E); printf("xslow = %f,\t yslow = %f,\t xfast = %f,\t yfast = %f\n", xslow,yslow,xfast,yfast); printf("xmin = %f,\t ymin = %f,\t xmax = %f,\t ymax = %f\n", xmin,ymin,xmax,ymax); /* Calculate the 1D wind solution at cell-interfaces */ for (i=il; i<=iu+1; i++) { memset(&(Wind[i]),0.0,sizeof(ConsS)); cc_pos(pG,i,js,ks,&x1,&x2,&x3); /* Want the solution at R-interfaces */ R0 = x1 - 0.5*pG->dx1; x = R0/R_A; /* Look for a sign change interval */ if (x < xslow) { sign_change(myfunc,yslow,10.0*ymax,x,&a,&b); sign_change(myfunc,b,10.0*ymax,x,&a,&b); } else if (x < 1.0) { sign_change(myfunc,1.0+TINY_NUMBER,yslow,x,&a,&b); } else if (x < xfast) { sign_change(myfunc,yfast,1.0-TINY_NUMBER,x,&a,&b); if (!sign_change(myfunc,b,1.0-TINY_NUMBER,x,&a,&b)) { a = yfast; b = 1.0-TINY_NUMBER; } } else { sign_change(myfunc,0.5*ymin,yfast,x,&a,&b); } /* Use bisection to find the root */ converged = bisection(myfunc,a,b,x,&y); if(!converged) { ath_error("[cylwindrotb]: Bisection did not converge!\n"); } /* Construct the solution */ rho = rho_A*y; Mdot = sqrt(R_A*SQR(rho_A)*GM*eta); Omega = sqrt((GM*omega)/pow(R_A,3)); K = (GM*theta)/(Gamma*pow(rho_A,Gamma_1)*R_A); Pgas = K*pow(rho,Gamma); vR = Mdot/(R0*rho); beta = sqrt(1.0/rho_A); BR = beta*rho*vR; vphi = R0*Omega*(1.0/SQR(x)-y)/(1.0-y); Bphi = beta*rho*(vphi-R0*Omega); Wind[i].d = rho; Wind[i].M1 = rho*vR; Wind[i].M2 = rho*vphi; Wind[i].M3 = rho*vz; Wind[i].B1c = BR; Wind[i].B2c = Bphi; Wind[i].B3c = 0.0; Wind[i].E = Pgas/Gamma_1 + 0.5*(SQR(Wind[i].B1c) + SQR(Wind[i].B2c) + SQR(Wind[i].B3c)) + 0.5*(SQR(Wind[i].M1 ) + SQR(Wind[i].M2 ) + SQR(Wind[i].M3 ))/Wind[i].d; } /* Average the wind solution across the zone for cc variables */ for (i=il; i<=iu; i++) { memset(&(pG->U[ks][js][i]),0.0,sizeof(ConsS)); cc_pos(pG,i,js,ks,&x1,&x2,&x3); lsf = (x1 - 0.5*pG->dx1)/x1; rsf = (x1 + 0.5*pG->dx1)/x1; pU = (Real*)&(pG->U[ks][js][i]); pUl = (Real*)&(Wind[i]); pUr = (Real*)&(Wind[i+1]); for (n=0; n<NWAVE; n++) { pU[n] = 0.5*(lsf*pUl[n] + rsf*pUr[n]); } pG->B1i[ks][js][i] = Wind[i].B1c; pG->B2i[ks][js][i] = 0.5*(lsf*Wind[i].B2c + rsf*Wind[i+1].B2c); pG->B3i[ks][js][i] = 0.5*(lsf*Wind[i].B3c + rsf*Wind[i+1].B3c); } /* Copy 1D solution across the grid and save */ for (k=kl; k<=ku; k++) { for (j=jl; j<=ju; j++) { for (i=il; i<=iu; i++) { pG->U[k][j][i] = pG->U[ks][js][i]; pG->B1i[k][j][i] = pG->B1i[ks][js][i]; pG->B2i[k][j][i] = pG->B2i[ks][js][i]; pG->B3i[k][j][i] = pG->B3i[ks][js][i]; RootSoln[k][j][i] = pG->U[ks][js][i]; } } } StaticGravPot = grav_pot; bvals_mhd_fun(pDomain,left_x1,do_nothing_bc); bvals_mhd_fun(pDomain,right_x1,do_nothing_bc); free_1d_array((void *)Wind); return; }