Small changes to channel example

2 files changed, 19 insertions, 7 deletions

diff --git a/tangle/LLBM/sdf.h b/tangle/LLBM/sdf.h
index 656c109..52db8cf 100644
--- a/tangle/LLBM/sdf.h
+++ b/tangle/LLBM/sdf.h
@@ -63,6 +63,15 @@ __device__ __host__ float sintersect(float a, float b, float k) {
   return lerp(b, a, h) + k*h*(1.f-h);
 }
 
+__device__ __host__ float3 twisted(float3 p, float k) {
+  float c = cos(k*p.y);
+  float s = sin(k*p.y);
+  float3  q = make_float3(0,0,p.y);
+  q.x = p.x*c + p.z*-s;
+  q.y = p.x*s + p.z* c;
+  return q;
+}
+
 }
 
 template <typename SDF>
diff --git a/tangle/channel-with-sphere.cu b/tangle/channel.cu
index 280a142..6a0f072 100644
--- a/tangle/channel-with-sphere.cu
+++ b/tangle/channel.cu
@@ -21,7 +21,7 @@ if (cuda::device::count() == 0) {
 }
 auto current = cuda::device::current::get();
 
-const descriptor::Cuboid<DESCRIPTOR> cuboid(448, 64, 64);
+const descriptor::Cuboid<DESCRIPTOR> cuboid(500, 100, 100);
 Lattice<DESCRIPTOR,T> lattice(cuboid);
 
 CellMaterials<DESCRIPTOR> materials(cuboid, [&cuboid](uint3 p) -> int {
@@ -46,9 +46,11 @@ for (std::size_t iX=0; iX < cuboid.nX; ++iX) {
 }
 
 auto obstacle = [cuboid] __host__ __device__ (float3 p) -> float {
-                  float3 q = p - make_float3(cuboid.nX/6, cuboid.nY/2, cuboid.nZ/2);
-                  return sdf::sphere(q, cuboid.nY/T{5});
-                };
+  p -= make_float3(cuboid.nX/5, cuboid.nY/2, cuboid.nZ/2);
+  float3 q = sdf::twisted(p, 0.01);
+  return sdf::sphere(p, cuboid.nY/3.5) + sin(0.2*q.x)*sin(0.2*q.y)*sin(0.2*q.z);
+};
+
 materials.sdf(obstacle, 0);
 SignedDistanceBoundary bouzidi(lattice, materials, obstacle, 1, 0);
 
@@ -66,10 +68,11 @@ renderer.add<QCriterionS>(lattice, bulk_mask, obstacle);
 renderer.add<CurlNormS>(lattice, bulk_mask, obstacle);
 renderer.add<VelocityNormS>(lattice, bulk_mask, obstacle);
 renderer.run([&](std::size_t iStep) {
-  const float tau = 0.51;
-  const float inflow = 0.05;
+  const float tau = 0.501;
+  const float smagorinsky = 0.1;
+  const float inflow = 0.04;
   
-  lattice.apply(Operator(BgkCollideO(), bulk_mask, tau),
+  lattice.apply(Operator(SmagorinskyBgkCollideO(), bulk_mask, tau, smagorinsky),
                 Operator(BounceBackFreeSlipO(), wall_mask_z, WallNormal<0,0,1>()),
                 Operator(BounceBackFreeSlipO(), wall_mask_y, WallNormal<0,1,0>()),
                 Operator(EquilibriumVelocityWallO(), inflow_mask, std::min(iStep*1e-4, 1.0)*inflow, WallNormal<1,0,0>()),