Create basic buoyancy term as node kernel, named buoyancy_density

include/node_kernels/MomentumBuoyancyNodeKernel.h

@@ -0,0 +1,60 @@
+// Copyright 2017 National Technology & Engineering Solutions of Sandia, LLC
+// (NTESS), National Renewable Energy Laboratory, University of Texas Austin,
+// Northwest Research Associates. Under the terms of Contract DE-NA0003525
+// with NTESS, the U.S. Government retains certain rights in this software.
+//
+// This software is released under the BSD 3-clause license. See LICENSE file
+// for more details.
+//
+
+#ifndef MOMENTUMBUOYANCYNODEKERNEL_h
+#define MOMENTUMBUOYANCYNODEKERNEL_h
+
+#include "node_kernels/NodeKernel.h"
+
+#include "stk_mesh/base/BulkData.hpp"
+#include "stk_mesh/base/Ngp.hpp"
+#include "stk_mesh/base/NgpField.hpp"
+#include "stk_mesh/base/Types.hpp"
+
+namespace sierra {
+namespace nalu {
+
+class SolutionOptions;
+
+class MomentumBuoyancyNodeKernel
+  : public NGPNodeKernel<MomentumBuoyancyNodeKernel>
+{
+public:
+  MomentumBuoyancyNodeKernel(
+    const stk::mesh::BulkData&, const SolutionOptions&);
+
+  MomentumBuoyancyNodeKernel() = delete;
+
+  KOKKOS_DEFAULTED_FUNCTION
+  virtual ~MomentumBuoyancyNodeKernel() = default;
+
+  virtual void setup(Realm&) override;
+
+  KOKKOS_FUNCTION
+  virtual void execute(
+    NodeKernelTraits::LhsType&,
+    NodeKernelTraits::RhsType&,
+    const stk::mesh::FastMeshIndex&) override;
+
+private:
+  stk::mesh::NgpField<double> dualNodalVolume_;
+  stk::mesh::NgpField<double> densityNp1_;
+  const int nDim_;
+  NodeKernelTraits::DblType rhoRef_;
+
+  unsigned dualNodalVolumeID_{stk::mesh::InvalidOrdinal};
+  unsigned densityNp1ID_{stk::mesh::InvalidOrdinal};
+
+  NALU_ALIGNED NodeKernelTraits::DblType gravity_[NodeKernelTraits::NDimMax];
+};
+
+} // namespace nalu
+} // namespace sierra
+
+#endif

reg_tests/test_files/VOFDroplet/VOFDroplet.norm.gold

@@ -1,3 +1,3 @@
-2.67343413675555e-05 11 0.0001
-6.859619665424383e-06 12 0.0002
-3.313464463487743e-06 13 0.0003
+2.673434136755543e-05 11 0.0001
+6.859619665424398e-06 12 0.0002
+3.313464463487801e-06 13 0.0003

reg_tests/test_files/VOFDroplet/VOFDroplet.yaml

@@ -120,7 +120,7 @@ realms:
 
         - source_terms:
             momentum:
-            - buoyancy
+            - buoyancy_density
 
         - user_constants:
             reference_density: 0.00

src/LowMachEquationSystem.C

@@ -91,6 +91,7 @@
 #include "node_kernels/MomentumBodyForceNodeKernel.h"
 #include "node_kernels/MomentumBodyForceBoxNodeKernel.h"
 #include "node_kernels/MomentumBoussinesqNodeKernel.h"
+#include "node_kernels/MomentumBuoyancyNodeKernel.h"
 #include "node_kernels/MomentumCoriolisNodeKernel.h"
 #include "node_kernels/MomentumMassBDFNodeKernel.h"
 #include "node_kernels/MomentumGclSrcNodeKernel.h"
@@ -1390,6 +1391,9 @@ MomentumEquationSystem::register_interior_algorithm(stk::mesh::Part* part)
         if (srcName == "buoyancy_boussinesq") {
           nodeAlg.add_kernel<MomentumBoussinesqNodeKernel>(
             realm_.bulk_data(), *realm_.solutionOptions_);
+        } else if (srcName == "buoyancy_density") {
+          nodeAlg.add_kernel<MomentumBuoyancyNodeKernel>(
+            realm_.bulk_data(), *realm_.solutionOptions_);
         } else if (srcName == "body_force") {
           const auto it =
             realm_.solutionOptions_->srcTermParamMap_.find("momentum");

src/node_kernels/CMakeLists.txt

@@ -6,6 +6,7 @@ target_sources(nalu PRIVATE
   ${CMAKE_CURRENT_SOURCE_DIR}/MomentumBodyForceNodeKernel.C
   ${CMAKE_CURRENT_SOURCE_DIR}/MomentumBodyForceBoxNodeKernel.C
   ${CMAKE_CURRENT_SOURCE_DIR}/MomentumBoussinesqNodeKernel.C
+  ${CMAKE_CURRENT_SOURCE_DIR}/MomentumBuoyancyNodeKernel.C
   ${CMAKE_CURRENT_SOURCE_DIR}/MomentumGclNodeKernel.C
   ${CMAKE_CURRENT_SOURCE_DIR}/MomentumMassBDFNodeKernel.C
   ${CMAKE_CURRENT_SOURCE_DIR}/MomentumActuatorNodeKernel.C

src/node_kernels/MomentumBuoyancyNodeKernel.C

@@ -0,0 +1,64 @@
+// Copyright 2017 National Technology & Engineering Solutions of Sandia, LLC
+// (NTESS), National Renewable Energy Laboratory, University of Texas Austin,
+// Northwest Research Associates. Under the terms of Contract DE-NA0003525
+// with NTESS, the U.S. Government retains certain rights in this software.
+//
+// This software is released under the BSD 3-clause license. See LICENSE file
+// for more details.
+//
+
+#include "node_kernels/MomentumBuoyancyNodeKernel.h"
+#include "Realm.h"
+
+#include "stk_mesh/base/MetaData.hpp"
+#include "stk_mesh/base/Types.hpp"
+#include "utils/StkHelpers.h"
+
+#include "SolutionOptions.h"
+
+namespace sierra {
+namespace nalu {
+
+MomentumBuoyancyNodeKernel::MomentumBuoyancyNodeKernel(
+  const stk::mesh::BulkData& bulk, const SolutionOptions& solnOpts)
+  : NGPNodeKernel<MomentumBuoyancyNodeKernel>(),
+    nDim_(bulk.mesh_meta_data().spatial_dimension()),
+    rhoRef_(solnOpts.referenceDensity_)
+{
+  const auto& meta = bulk.mesh_meta_data();
+
+  dualNodalVolumeID_ = get_field_ordinal(meta, "dual_nodal_volume");
+  densityNp1ID_ = get_field_ordinal(meta, "density");
+
+  const std::vector<double>& solnOptsGravity =
+    solnOpts.get_gravity_vector(nDim_);
+  for (int i = 0; i < nDim_; i++)
+    gravity_[i] = solnOptsGravity[i];
+}
+
+void
+MomentumBuoyancyNodeKernel::setup(Realm& realm)
+{
+  const auto& fieldMgr = realm.ngp_field_manager();
+  dualNodalVolume_ = fieldMgr.get_field<double>(dualNodalVolumeID_);
+  densityNp1_ = fieldMgr.get_field<double>(densityNp1ID_);
+}
+
+KOKKOS_FUNCTION
+void
+MomentumBuoyancyNodeKernel::execute(
+  NodeKernelTraits::LhsType&,
+  NodeKernelTraits::RhsType& rhs,
+  const stk::mesh::FastMeshIndex& node)
+{
+  const NodeKernelTraits::DblType rhoNp1 = densityNp1_.get(node, 0);
+  const NodeKernelTraits::DblType dualVolume = dualNodalVolume_.get(node, 0);
+  const double fac = (rhoNp1 - rhoRef_) * dualVolume;
+
+  for (int i = 0; i < nDim_; ++i) {
+    rhs(i) += fac * gravity_[i];
+  }
+}
+
+} // namespace nalu
+} // namespace sierra