/*******************************************************************************
* This file is part of SWIFT.
* Copyright (c) 2023 Matthieu Schaller (schaller@strw.leidenuniv.nl)
* Copyright (c) 2024 Nikyta Shchutksyi (shchutskyi@lorentz.leidenuniv.nl)
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see .
*
******************************************************************************/
#ifndef SWIFT_FORCING_ABC_FLOW_H
#define SWIFT_FORCING_ABC_FLOW_H
/* Config parameters. */
#include
/* Standard includes. */
#include
/* Local includes. */
#include "error.h"
#include "parser.h"
#include "part.h"
#include "physical_constants.h"
#include "space.h"
#include "units.h"
/**
* @brief Forcing Term Properties
*/
struct forcing_terms {
/*! Reference velocity (internal units) */
float u0;
/*! Velocity scaling along the z direction */
float Vz_factor;
/*! Wavenumber of the flow */
float kv;
/*! ABC flow coefficients */
float A, B, C;
};
/**
* @brief Computes the forcing terms.
*
* Based on David Galloway (2012) ABC flows then and now, Geophysical &
* Astrophysical Fluid Dynamics, 106:4-5, 450-467 This version differs from the
* paper by imposing normalized velocity
*
* @param time The current time.
* @param terms The properties of the forcing terms.
* @param s The #space we act on.
* @param phys_const The physical constants in internal units.
* @param p Pointer to the particle data.
* @param xp Pointer to the extended particle data.
*/
__attribute__((always_inline)) INLINE static void forcing_terms_apply(
const double time, const struct forcing_terms* terms, const struct space* s,
const struct phys_const* phys_const, struct part* p, struct xpart* xp) {
const double L = s->dim[0];
const float u0 = terms->u0;
const float A = terms->A;
const float B = terms->B;
const float C = terms->C;
const float Norm = 1 / sqrt(A * A + B * B + C * C);
const float Vz_factor = terms->Vz_factor;
const double k0 = (2. * M_PI / L) * terms->kv;
double v_ABC[3];
/* Eq. 2 of David Galloway (2012) ABC flows then and now, Geophysical &
* Astrophysical Fluid Dynamics, 106:4-5, 450-467 */
// Velocity normalized such that rms = u0
v_ABC[0] = u0 * Norm * (A * sin(k0 * p->x[2]) + C * cos(k0 * p->x[1]));
v_ABC[1] = u0 * Norm * (B * sin(k0 * p->x[0]) + A * cos(k0 * p->x[2]));
v_ABC[2] = u0 * Norm * (C * sin(k0 * p->x[1]) + B * cos(k0 * p->x[0]));
/* Force the velocity and possibly scale the z-direction */
xp->v_full[0] = v_ABC[0];
xp->v_full[1] = v_ABC[1];
xp->v_full[2] = v_ABC[2] * Vz_factor;
}
/**
* @brief Computes the time-step condition due to the forcing terms.
*
* Nothing to do here. --> Return FLT_MAX.
*
* @param time The current time.
* @param terms The properties of the forcing terms.
* @param phys_const The physical constants in internal units.
* @param p Pointer to the particle data.
* @param xp Pointer to the extended particle data.
*/
__attribute__((always_inline)) INLINE static float forcing_terms_timestep(
double time, const struct forcing_terms* terms,
const struct phys_const* phys_const, const struct part* p,
const struct xpart* xp) {
return FLT_MAX;
}
/**
* @brief Prints the properties of the forcing terms to stdout.
*
* @param terms The #forcing_terms properties of the run.
*/
static INLINE void forcing_terms_print(const struct forcing_terms* terms) {
message("Forcing terms is 'ABC flow'. U0: %.5f / Vz factor: %.5f.", terms->u0,
terms->Vz_factor);
message("Run using ABC parameters: A = %.5f, B = %.5f, C = %.5f", terms->A,
terms->B, terms->C);
}
/**
* @brief Initialises the forcing term properties
*
* @param parameter_file The parsed parameter file
* @param phys_const Physical constants in internal units
* @param us The current internal system of units
* @param s The #space object.
* @param terms The forcing term properties to initialize
*/
static INLINE void forcing_terms_init(struct swift_params* parameter_file,
const struct phys_const* phys_const,
const struct unit_system* us,
const struct space* s,
struct forcing_terms* terms) {
terms->u0 = parser_get_param_double(parameter_file, "ABC_Flow_Forcing:u0");
terms->Vz_factor = parser_get_opt_param_float(
parameter_file, "ABC_Flow_Forcing:Vz_factor", 1.f);
terms->kv = parser_get_param_double(parameter_file, "ABC_Flow_Forcing:kv");
terms->A = parser_get_param_double(parameter_file, "ABC_Flow_Forcing:A");
terms->B = parser_get_param_double(parameter_file, "ABC_Flow_Forcing:B");
terms->C = parser_get_param_double(parameter_file, "ABC_Flow_Forcing:C");
}
#endif /* SWIFT_FORCING_ABC_FLOW_H */