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THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. ! ! //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// ! */ #include "SELF_GPU_Macros.h" __global__ void boundaryflux_LinearEuler2D_kernel(real *fb, real *extfb, real *nhat, real *nmag, real *flux, real rho0, int ndof){ // Characteristic-decomposition (impedance-matched) interface flux for // linear acoustics with possibly discontinuous sound speed. See the // CPU-side Fortran subroutine riemannflux2d_LinearEuler2D_t for the // derivation. This replaces LLF, which over-dissipates the tangential // and entropy modes and fails to stably handle the impedance mismatch // at high polynomial order (aliasing instability). uint32_t idof = threadIdx.x + blockIdx.x*blockDim.x; if( idof < ndof ){ real nx = nhat[idof]; real ny = nhat[idof+ndof]; real nm = nmag[idof]; real cL = fb[idof + 4*ndof]; real cR = extfb[idof + 4*ndof]; real ZL = rho0*cL; real ZR = rho0*cR; real unL = fb[idof + ndof]*nx + fb[idof + 2*ndof]*ny; real unR = extfb[idof + ndof]*nx + extfb[idof + 2*ndof]*ny; real pL = fb[idof + 3*ndof]; real pR = extfb[idof + 3*ndof]; real un_star = (ZL*unL + ZR*unR + (pL - pR)) / (ZL + ZR); real p_star = (ZR*pL + ZL*pR + ZL*ZR*(unL - unR)) / (ZL + ZR); real c2_avg = 0.5*(cL*cL + cR*cR); flux[idof] = (rho0*un_star) * nm; // density flux[idof + ndof] = (p_star*nx/rho0) * nm; // u flux[idof + 2*ndof] = (p_star*ny/rho0) * nm; // v flux[idof + 3*ndof] = (rho0*c2_avg*un_star) * nm; // pressure flux[idof + 4*ndof] = 0.0; // sound speed } } extern "C" { void boundaryflux_LinearEuler2D_gpu(real *fb, real *extfb,real *nhat, real *nmag, real *flux, real rho0, int N, int nel, int nvar){ int threads_per_block = 256; uint32_t ndof = (N+1)*4*nel; int nblocks_x = ndof/threads_per_block +1; dim3 nblocks(nblocks_x,nvar,1); dim3 nthreads(threads_per_block,1,1); boundaryflux_LinearEuler2D_kernel<<<nblocks,nthreads>>>(fb,extfb,nhat,nmag,flux,rho0,ndof); } } __global__ void fluxmethod_LinearEuler2D_gpukernel(real *solution, real *flux, real rho0, int ndof, int nvar){ uint32_t idof = threadIdx.x + blockIdx.x*blockDim.x; if( idof < ndof ){ real u = solution[idof + ndof]; real v = solution[idof + 2*ndof]; real p = solution[idof + 3*ndof]; real c = solution[idof + 4*ndof]; flux[idof + ndof*(0 + nvar*0)] = rho0*u; // density, x flux ; rho0*u flux[idof + ndof*(0 + nvar*1)] = rho0*v; // density, y flux ; rho0*v flux[idof + ndof*(1 + nvar*0)] = p/rho0; // x-velocity, x flux; p/rho0 flux[idof + ndof*(1 + nvar*1)] = 0.0; // x-velocity, y flux; 0 flux[idof + ndof*(2 + nvar*0)] = 0.0; // y-velocity, x flux; 0 flux[idof + ndof*(2 + nvar*1)] = p/rho0; // y-velocity, y flux; p/rho0 flux[idof + ndof*(3 + nvar*0)] = c*c*rho0*u; // pressure, x flux : rho0*c^2*u flux[idof + ndof*(3 + nvar*1)] = c*c*rho0*v; // pressure, y flux : rho0*c^2*v flux[idof + ndof*(4 + nvar*0)] = 0.0; // sound speed, x flux; 0 (c held fixed in time) flux[idof + ndof*(4 + nvar*1)] = 0.0; // sound speed, y flux; 0 (c held fixed in time) } } extern "C" { void fluxmethod_LinearEuler2D_gpu(real *solution, real *flux, real rho0, int N, int nel, int nvar){ int ndof = (N+1)*(N+1)*nel; int threads_per_block = 256; int nblocks_x = ndof/threads_per_block +1; fluxmethod_LinearEuler2D_gpukernel<<<dim3(nblocks_x,1,1), dim3(threads_per_block,1,1), 0, 0>>>(solution,flux,rho0,ndof,nvar); } } // ============================================================ // No-normal-flow BC kernel for 2D Linear Euler // Operates on pre-filtered boundary faces via elements/sides arrays // ============================================================ __global__ void hbc2d_nonormalflow_lineareuler2d_kernel( real *extBoundary, real *boundary, real *nhat, int *elements, int *sides, int nBoundaries, int N, int nel) { uint32_t idof = threadIdx.x + blockIdx.x*blockDim.x; uint32_t total_dofs = nBoundaries * (N+1); if(idof < total_dofs){ uint32_t i = idof % (N+1); uint32_t n = idof / (N+1); uint32_t e1 = elements[n] - 1; // Fortran 1-based to C 0-based uint32_t s1 = sides[n] - 1; real u = boundary[SCB_2D_INDEX(i,s1,e1,1,N,nel)]; real v = boundary[SCB_2D_INDEX(i,s1,e1,2,N,nel)]; real nx = nhat[VEB_2D_INDEX(i,s1,e1,0,0,N,nel,1)]; real ny = nhat[VEB_2D_INDEX(i,s1,e1,0,1,N,nel,1)]; extBoundary[SCB_2D_INDEX(i,s1,e1,0,N,nel)] = boundary[SCB_2D_INDEX(i,s1,e1,0,N,nel)]; // density extBoundary[SCB_2D_INDEX(i,s1,e1,1,N,nel)] = (ny*ny-nx*nx)*u - 2.0*nx*ny*v; // u extBoundary[SCB_2D_INDEX(i,s1,e1,2,N,nel)] = (nx*nx-ny*ny)*v - 2.0*nx*ny*u; // v extBoundary[SCB_2D_INDEX(i,s1,e1,3,N,nel)] = boundary[SCB_2D_INDEX(i,s1,e1,3,N,nel)]; // pressure extBoundary[SCB_2D_INDEX(i,s1,e1,4,N,nel)] = boundary[SCB_2D_INDEX(i,s1,e1,4,N,nel)]; // c } } extern "C" { void hbc2d_nonormalflow_lineareuler2d_gpu( real *extBoundary, real *boundary, real *nhat, int *elements, int *sides, int nBoundaries, int N, int nel) { int threads_per_block = 256; int total_dofs = nBoundaries * (N+1); int nblocks_x = total_dofs/threads_per_block + 1; hbc2d_nonormalflow_lineareuler2d_kernel<<<dim3(nblocks_x,1,1), dim3(threads_per_block,1,1), 0, 0>>>(extBoundary, boundary, nhat, elements, sides, nBoundaries, N, nel); } } // ============================================================ // Radiation BC kernel for 2D Linear Euler // Sets density/u/v/p extBoundary = 0 on pre-filtered boundary // faces. The sound speed (variable 4) is copied from the // interior side so that face Riemann fluxes see a consistent c. // ============================================================ __global__ void hbc2d_radiation_lineareuler2d_kernel( real *extBoundary, real *boundary, int *elements, int *sides, int nBoundaries, int N, int nel) { uint32_t idof = threadIdx.x + blockIdx.x*blockDim.x; uint32_t total_dofs = nBoundaries * (N+1); if(idof < total_dofs){ uint32_t i = idof % (N+1); uint32_t n = idof / (N+1); uint32_t e1 = elements[n] - 1; uint32_t s1 = sides[n] - 1; extBoundary[SCB_2D_INDEX(i,s1,e1,0,N,nel)] = 0.0; extBoundary[SCB_2D_INDEX(i,s1,e1,1,N,nel)] = 0.0; extBoundary[SCB_2D_INDEX(i,s1,e1,2,N,nel)] = 0.0; extBoundary[SCB_2D_INDEX(i,s1,e1,3,N,nel)] = 0.0; extBoundary[SCB_2D_INDEX(i,s1,e1,4,N,nel)] = boundary[SCB_2D_INDEX(i,s1,e1,4,N,nel)]; // c preserved } } extern "C" { void hbc2d_radiation_lineareuler2d_gpu( real *extBoundary, real *boundary, int *elements, int *sides, int nBoundaries, int N, int nel) { int threads_per_block = 256; int total_dofs = nBoundaries * (N+1); int nblocks_x = total_dofs/threads_per_block + 1; hbc2d_radiation_lineareuler2d_kernel<<<dim3(nblocks_x,1,1), dim3(threads_per_block,1,1), 0, 0>>>(extBoundary, boundary, elements, sides, nBoundaries, N, nel); } }