Routines to use DPD as thermostat or pair force [42]. More...

#include <config/config.hpp>
#include "BoxGeometry.hpp"
#include "Particle.hpp"
#include "nonbonded_interactions/nonbonded_interaction_data.hpp"
#include "system/System.hpp"
#include "thermostat.hpp"
#include <utils/Vector.hpp>
#include <cmath>

Include dependency graph for dpd.hpp:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Namespaces
namespace	boost

namespace	boost::mpi

Functions
Utils::Vector3d	dpd_pair_force (DPDParameters const &params, Utils::Vector3d const &v, double dist, Utils::Vector3d const &noise)

Utils::Vector3d	dpd_pair_force (Utils::Vector3d const &p1_position, Utils::Vector3d const &p1_velocity, int const &p1_id, Utils::Vector3d const &p2_position, Utils::Vector3d const &p2_velocity, int const &p2_id, DPDThermostat const &dpd, BoxGeometry const &box_geo, IA_parameters const &ia_params, Utils::Vector3d const &d, double dist, double dist2)

Utils::Vector9d	dpd_stress (System::System &system, boost::mpi::communicator const &comm)
	Viscous stress tensor of the DPD interaction.

Utils::Vector9d	dpd_pressure_local (System::System &system)
	Local contribution to the pressure tensor.

Detailed Description

Routines to use DPD as thermostat or pair force [42].

Implementation in dpd.cpp.

Definition in file dpd.hpp.

Function Documentation

◆ dpd_pair_force() [1/2]

Utils::Vector3d dpd_pair_force	(	DPDParameters const &	params,
		Utils::Vector3d const &	v,
		double	dist,
		Utils::Vector3d const &	noise
	)

inline

Definition at line 49 of file dpd.hpp.

References DPDParameters::cutoff, DPDParameters::gamma, DPDParameters::k, DPDParameters::pref, stream, and DPDParameters::wf.

◆ dpd_pair_force() [2/2]

Utils::Vector3d dpd_pair_force	(	Utils::Vector3d const &	p1_position,
		Utils::Vector3d const &	p1_velocity,
		int const &	p1_id,
		Utils::Vector3d const &	p2_position,
		Utils::Vector3d const &	p2_velocity,
		int const &	p2_id,
		DPDThermostat const &	dpd,
		BoxGeometry const &	box_geo,
		IA_parameters const &	ia_params,
		Utils::Vector3d const &	d,
		double	dist,
		double	dist2
	)

Definition at line 79 of file dpd.cpp.

References dpd_noise(), dpd_pair_force(), P, stream, and BoxGeometry::velocity_difference().

Referenced by add_non_bonded_pair_force_with_p(), dpd_pair_force(), dpd_viscous_stress_local(), Constraints::ShapeBasedConstraint::force(), and ForcesKernel::operator()().

◆ dpd_pressure_local()

Utils::Vector9d dpd_pressure_local ( System::System & system )

Local contribution to the pressure tensor.

Needs to be rescaled by the box volume.

Definition at line 139 of file dpd.cpp.

References dpd_viscous_stress_local(), Utils::flatten(), and stream.

Referenced by System::System::calculate_pressure().

◆ dpd_stress()

Utils::Vector9d dpd_stress	(	System::System &	system,
		boost::mpi::communicator const &	comm
	)

Viscous stress tensor of the DPD interaction.

This calculates the total viscous stress contribution of the DPD interaction. It contains only the dissipative contributions of the interaction without noise. It's calculated as the sum over all pair virials as

\[ \sigma^{\nu\mu} = V^{-1}\sum_i \sum_{j < i} r_{i,j}^{\nu} (- \gamma_{i,j} v_{i,j})^{\mu} \]

where \(\gamma_{i,j}\) is the (in general tensor valued) DPD friction coefficient for particles i and j, \(v_{i,j}\), \(r_{i,j}\) are their relative velocity and distance and \(V\) is the box volume.

Returns: Stress tensor contribution.

Definition at line 159 of file dpd.cpp.