Potentials.h

Go to the documentation of this file.

#pragma once
 
 
#include "physics/Functions.h"
#include "sph/equations/EquationTerm.h"
 
NAMESPACE_SPH_BEGIN
 
template <typename TFunctor>
class ExternalForce : public IEquationTerm {
private:
    std::remove_reference_t<TFunctor> functor;
 
public:
    ExternalForce(TFunctor&& functor)
        : functor(std::forward<TFunctor>(functor)) {}
 
    virtual void setDerivatives(DerivativeHolder& UNUSED(derivatives),
        const RunSettings& UNUSED(settings)) override {}
 
    virtual void initialize(IScheduler& UNUSED(scheduler),
        Storage& UNUSED(storage),
        const Float UNUSED(t)) override {}
 
    virtual void finalize(IScheduler& UNUSED(scheduler), Storage& storage, const Float t) override {
        ArrayView<Vector> r, v, dv;
        tie(r, v, dv) = storage.getAll<Vector>(QuantityId::POSITION);
        for (Size i = 0; i < r.size(); ++i) {
            dv[i] += functor(r[i], t);
        }
    }
 
    virtual void create(Storage& UNUSED(storage), IMaterial& UNUSED(material)) const override {}
};
 
template <typename TFunctor>
EquationHolder makeExternalForce(TFunctor&& functor) {
    return EquationHolder(makeShared<ExternalForce<TFunctor>>(std::forward<TFunctor>(functor)));
}
 
class InertialForce : public IEquationTerm {
private:
    Vector omega;
 
public:
    InertialForce(const Vector omega)
        : omega(omega) {}
 
    virtual void setDerivatives(DerivativeHolder& UNUSED(derivatives),
        const RunSettings& UNUSED(settings)) override {}
 
    virtual void initialize(IScheduler& UNUSED(scheduler),
        Storage& UNUSED(storage),
        const Float UNUSED(t)) override {}
 
    virtual void finalize(IScheduler& UNUSED(scheduler), Storage& storage, const Float UNUSED(t)) override {
        ArrayView<Vector> r, v, dv;
        tie(r, v, dv) = storage.getAll<Vector>(QuantityId::POSITION);
        for (Size i = 0; i < r.size(); ++i) {
            dv[i] -= 2._f * cross(omega, v[i]) + cross(omega, cross(omega, r[i]));
            // no energy term - energy is not generally conserved when external force is used
        }
    }
 
    virtual void create(Storage& UNUSED(storage), IMaterial& UNUSED(material)) const override {}
};
 
NAMESPACE_SPH_END