diff options
| -rw-r--r-- | lbm.org | 26 | ||||
| -rw-r--r-- | tangle/magnus.cu | 13 |
2 files changed, 25 insertions, 14 deletions
@@ -5257,7 +5257,7 @@ After setting up the lattice we define the relaxation time for the BGK collision bulk and the desired rotation and inflow velocities. #+BEGIN_SRC cpp :tangle tangle/magnus.cu -const float tau = 0.54; +const float tau = 0.52; const float u_inflow = 0.02; const float u_rotate = 0.08; #+END_SRC @@ -5363,7 +5363,9 @@ renderSliceViewToTexture<<< dim3(cuboid.nX / 32 + 1, cuboid.nY / 32 + 1), dim3(32,32) >>>(cuboid.nX, cuboid.nY, - slice, + [cuboid] __device__ (int iX, int iY) -> std::size_t { + return descriptor::gid(cuboid,iX,cuboid.nY-1-iY); + }, [u,u_rotate] __device__ (std::size_t gid) -> float { return length(make_float2(u[2*gid+0], u[2*gid+1])) / u_rotate; }, @@ -5373,21 +5375,27 @@ renderSliceViewToTexture<<< window.getRenderSurface()); #+END_SRC +The render target is provided by our =RenderWindow= class. We also need +variables for storing the colormap and buffers for storing the computed +moments. + #+BEGIN_SRC cpp :tangle tangle/magnus.cu RenderWindow window("Magnus"); cudaSurfaceObject_t colormap; ColorPalette palette(colormap); -auto slice = [cuboid] __device__ (int iX, int iY) -> std::size_t { - return descriptor::gid(cuboid,iX,cuboid.nY-1-iY); - }; DeviceBuffer<T> moments_rho(cuboid.volume); DeviceBuffer<T> moments_u(2*cuboid.volume); T* u = moments_u.device(); -std::size_t iStep = 0; +#+END_SRC +Finally we run the simulation as long as the window is open +while periodically calling the visualization code. + +#+BEGIN_SRC cpp :tangle tangle/magnus.cu +std::size_t iStep = 0; while (window.isOpen()) { <<magnus-simulation-step>> - if (iStep % 100 == 0) { + if (iStep % 200 == 0) { cudaDeviceSynchronize(); <<magnus-visualization-step>> window.draw([&]() { @@ -5401,6 +5409,10 @@ while (window.isOpen()) { } #+END_SRC +#+BEGIN_EXPORT html +<video style="width:100%" src="https://literatelb.org/media/magnus.webm" playsinline muted controls loop/> +#+END_EXPORT + ** Flow around a Sphere This example models a channel flow around a spherical obstacle. diff --git a/tangle/magnus.cu b/tangle/magnus.cu index aa31ba1..5800cd8 100644 --- a/tangle/magnus.cu +++ b/tangle/magnus.cu @@ -18,7 +18,7 @@ cudaSetDevice(0); const descriptor::Cuboid<DESCRIPTOR> cuboid(1200, 500); Lattice<DESCRIPTOR,T> lattice(cuboid); -const float tau = 0.54; +const float tau = 0.52; const float u_inflow = 0.02; const float u_rotate = 0.08; @@ -74,14 +74,11 @@ cudaDeviceSynchronize(); RenderWindow window("Magnus"); cudaSurfaceObject_t colormap; ColorPalette palette(colormap); -auto slice = [cuboid] __device__ (int iX, int iY) -> std::size_t { - return descriptor::gid(cuboid,iX,cuboid.nY-1-iY); - }; DeviceBuffer<T> moments_rho(cuboid.volume); DeviceBuffer<T> moments_u(2*cuboid.volume); T* u = moments_u.device(); -std::size_t iStep = 0; +std::size_t iStep = 0; while (window.isOpen()) { lattice.apply(Operator(BgkCollideO(), bulk_mask, tau), Operator(BounceBackFreeSlipO(), wall_mask, WallNormal<0,1>()), @@ -90,14 +87,16 @@ while (window.isOpen()) { Operator(BounceBackO(), edge_mask)); lattice.apply<BouzidiO>(bouzidi.getCount(), bouzidi.getConfig()); lattice.stream(); - if (iStep % 100 == 0) { + if (iStep % 200 == 0) { cudaDeviceSynchronize(); lattice.inspect<CollectMomentsF>(bulk_mask, moments_rho.device(), moments_u.device()); renderSliceViewToTexture<<< dim3(cuboid.nX / 32 + 1, cuboid.nY / 32 + 1), dim3(32,32) >>>(cuboid.nX, cuboid.nY, - slice, + [cuboid] __device__ (int iX, int iY) -> std::size_t { + return descriptor::gid(cuboid,iX,cuboid.nY-1-iY); + }, [u,u_rotate] __device__ (std::size_t gid) -> float { return length(make_float2(u[2*gid+0], u[2*gid+1])) / u_rotate; }, |