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Diffstat (limited to 'Source/Initialization/InjectorDensity.H')
| -rw-r--r-- | Source/Initialization/InjectorDensity.H | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/Source/Initialization/InjectorDensity.H b/Source/Initialization/InjectorDensity.H new file mode 100644 index 000000000..b7f5c26eb --- /dev/null +++ b/Source/Initialization/InjectorDensity.H @@ -0,0 +1,202 @@ +#ifndef INJECTOR_DENSITY_H_ +#define INJECTOR_DENSITY_H_ + +#include <AMReX_Gpu.H> +#include <AMReX_Dim3.H> +#include <GpuParser.H> +#include <CustomDensityProb.H> +#include <WarpXConst.H> + +// struct whose getDensity returns constant density. +struct InjectorDensityConstant +{ + InjectorDensityConstant (amrex::Real a_rho) noexcept : m_rho(a_rho) {} + + AMREX_GPU_HOST_DEVICE + amrex::Real + getDensity (amrex::Real, amrex::Real, amrex::Real) const noexcept + { + return m_rho; + } + +private: + amrex::Real m_rho; +}; + +// struct whose getDensity returns local density computed from parser. +struct InjectorDensityParser +{ + InjectorDensityParser (WarpXParser const& a_parser) noexcept + : m_parser(a_parser) {} + + AMREX_GPU_HOST_DEVICE + amrex::Real + getDensity (amrex::Real x, amrex::Real y, amrex::Real z) const noexcept + { + return m_parser(x,y,z); + } + + // InjectorDensityParser constructs this GpuParser from WarpXParser. + GpuParser m_parser; +}; + +// struct whose getDensity returns local density computed from predefined profile. +struct InjectorDensityPredefined +{ + InjectorDensityPredefined (std::string const& a_species_name) noexcept; + + void clear (); + + AMREX_GPU_HOST_DEVICE + amrex::Real + getDensity (amrex::Real x, amrex::Real y, amrex::Real z) const noexcept + { + // Choices for profile are: + // - parabolic_channel + switch (profile) + { + case Profile::parabolic_channel: + { + amrex::Real z_start = p[0]; + amrex::Real ramp_up = p[1]; + amrex::Real plateau = p[2]; + amrex::Real ramp_down = p[3]; + amrex::Real rc = p[4]; + amrex::Real n0 = p[5]; + amrex::Real n; + amrex::Real kp = PhysConst::q_e/PhysConst::c + *std::sqrt( n0/(PhysConst::m_e*PhysConst::ep0) ); + + if ((z-z_start)>=0 and + (z-z_start)<ramp_up ) { + n = (z-z_start)/ramp_up; + } else if ((z-z_start)>=ramp_up and + (z-z_start)< ramp_up+plateau ) { + n = 1.; + } else if ((z-z_start)>=ramp_up+plateau and + (z-z_start)< ramp_up+plateau+ramp_down) { + n = 1.-((z-z_start)-ramp_up-plateau)/ramp_down; + } else { + n = 0.; + } + n *= n0*(1.+4.*(x*x+y*y)/(kp*kp*rc*rc*rc*rc)); + return n; + } + default: + amrex::Abort("InjectorDensityPredefined: how did we get here?"); + return 0.0; + } + } + +private: + enum struct Profile { null, parabolic_channel }; + Profile profile; + amrex::Real* p; +}; + +// Base struct for density injector. +// InjectorDensity contains a union (called Object) that holds any one +// instance of: +// - InjectorDensityConstant : to generate constant density; +// - InjectorDensityParser : to generate density from parser; +// - InjectorDensityCustom : to generate density from custom profile; +// - InjectorDensityPredefined: to generate density from predefined profile; +// The choice is made at runtime, depending in the constructor called. +// This mimics virtual functions, except the struct is stored in managed memory +// and member functions are made __host__ __device__ to run on CPU and GPU. +// This struct inherits from amrex::Gpu::Managed to provide new and delete +// operators in managed memory when running on GPU. Nothing special on CPU. +struct InjectorDensity + : public amrex::Gpu::Managed +{ + // This constructor stores a InjectorDensityConstant in union object. + InjectorDensity (InjectorDensityConstant* t, amrex::Real a_rho) + : type(Type::constant), + object(t,a_rho) + { } + + // This constructor stores a InjectorDensityParser in union object. + InjectorDensity (InjectorDensityParser* t, WarpXParser const& a_parser) + : type(Type::parser), + object(t,a_parser) + { } + + // This constructor stores a InjectorDensityCustom in union object. + InjectorDensity (InjectorDensityCustom* t, std::string const& a_species_name) + : type(Type::custom), + object(t,a_species_name) + { } + + // This constructor stores a InjectorDensityPredefined in union object. + InjectorDensity (InjectorDensityPredefined* t, std::string const& a_species_name) + : type(Type::predefined), + object(t,a_species_name) + { } + + // Explicitly prevent the compiler from generating copy constructors + // and copy assignment operators. + InjectorDensity (InjectorDensity const&) = delete; + InjectorDensity (InjectorDensity&&) = delete; + void operator= (InjectorDensity const&) = delete; + void operator= (InjectorDensity &&) = delete; + + ~InjectorDensity (); + + std::size_t sharedMemoryNeeded () const noexcept; + + // call getDensity from the object stored in the union + // (the union is called Object, and the instance is called object). + AMREX_GPU_HOST_DEVICE + amrex::Real + getDensity (amrex::Real x, amrex::Real y, amrex::Real z) const noexcept + { + switch (type) + { + case Type::parser: + { + return object.parser.getDensity(x,y,z); + } + case Type::constant: + { + return object.constant.getDensity(x,y,z); + } + case Type::custom: + { + return object.custom.getDensity(x,y,z); + } + case Type::predefined: + { + return object.predefined.getDensity(x,y,z); + } + default: + { + amrex::Abort("InjectorDensity: unknown type"); + return 0.0; + } + } + } + +private: + enum struct Type { constant, custom, predefined, parser }; + Type type; + + // An instance of union Object constructs and stores any one of + // the objects declared (constant or parser or custom or predefined). + union Object { + Object (InjectorDensityConstant*, amrex::Real a_rho) noexcept + : constant(a_rho) {} + Object (InjectorDensityParser*, WarpXParser const& a_parser) noexcept + : parser(a_parser) {} + Object (InjectorDensityCustom*, std::string const& a_species_name) noexcept + : custom(a_species_name) {} + Object (InjectorDensityPredefined*, std::string const& a_species_name) noexcept + : predefined(a_species_name) {} + InjectorDensityConstant constant; + InjectorDensityParser parser; + InjectorDensityCustom custom; + InjectorDensityPredefined predefined; + }; + Object object; +}; + +#endif |