diff options
| -rw-r--r-- | c++/descriptor.h | 1 | ||||
| -rw-r--r-- | c++/examples/cavity_2d.cpp | 24 |
2 files changed, 15 insertions, 10 deletions
diff --git a/c++/descriptor.h b/c++/descriptor.h index fad9bf2..63d6a5c 100644 --- a/c++/descriptor.h +++ b/c++/descriptor.h @@ -68,6 +68,7 @@ public: 2 }; + static constexpr typename saw::native_data_type<T>::type inv_cs2 = 3.0; static constexpr typename saw::native_data_type<T>::type cs2 = 1./3.; }; } diff --git a/c++/examples/cavity_2d.cpp b/c++/examples/cavity_2d.cpp index 00970a2..d603092 100644 --- a/c++/examples/cavity_2d.cpp +++ b/c++/examples/cavity_2d.cpp @@ -136,13 +136,13 @@ public: typename std::array<saw::native_data_type<sch::T>::type,Desc::Q> eq; for(std::size_t i = 0; i < eq.size(); ++i){ - auto vel_c = (vel[0]*dfi::directions[i][0] + vel[1]*dfi::directions[i][1]); + auto vel_c = 3.0 * (vel[0]*dfi::directions[i][0] + vel[1]*dfi::directions[i][1]); auto vel_c_cs2 = vel_c / dfi::cs2; eq[i] = dfi::weights[i] * rho * ( 1 + vel_c_cs2 - + vel_c_cs2 * vel_c_cs2 / 2. - - ( vel[0] * vel[0] + vel[1] * vel[1] ) / ( 2. * dfi::cs2 ) + + vel_c_cs2 * vel_c_cs2 * 0.5 + - 3.0 * ( vel[0] * vel[0] + vel[1] * vel[1] ) / ( 2. * dfi::cs2 ) ); } @@ -184,8 +184,8 @@ public: } constexpr size_t dim_size = 2; -constexpr size_t dim_x = 32; -constexpr size_t dim_y = 32; +constexpr size_t dim_x = 16; +constexpr size_t dim_y = 16; struct rectangle { std::array<size_t,4> data_; @@ -246,7 +246,7 @@ void lbm_step( using dfi = df_info<sch::T,sch::D2Q5>; collision<sch::D2Q5> coll; - coll.relaxation_ = 0.6; + coll.relaxation_ = 1.0; bounce_back<sch::D2Q5> bb; cavity_boundary<sch::D2Q5> bb_lid; @@ -262,10 +262,10 @@ void lbm_step( coll.apply(df); break; case 2u: - bb.apply(df); + bb_lid.apply(df); break; case 3u: - bb_lid.apply(df); + bb.apply(df); break; } }, old_latt); @@ -301,10 +301,12 @@ int main(){ * Set meta information describing what this cell is */ set_geometry(old_lattice); + set_geometry(new_lattice); /** * */ set_initial_conditions(old_lattice); + set_initial_conditions(new_lattice); /** * Timeloop @@ -336,14 +338,13 @@ int main(){ } }, old_lattice); - uint64_t lattice_steps = 32; + uint64_t lattice_steps = 1024u; bool even_step = true; for(uint64_t step = 0; step < lattice_steps; ++step){ auto& old_lat = even_step ? old_lattice : new_lattice; auto& new_lat = even_step ? new_lattice : old_lattice; - lbm_step(old_lat, new_lat); std::cout<<"\n"; apply_for_cells([](auto& cell, std::size_t i, std::size_t j){ @@ -356,7 +357,10 @@ int main(){ std::cout<<"\n"; } }, old_lat); + + lbm_step(old_lat, new_lat); + std::cout<<"Even: "<<(even_step ? "true" : "false")<<std::endl; even_step = !even_step; } |