Class Viscosity_Takahashi2015

Inheritance Relationships

Base Type

Class Documentation

class SPH::Viscosity_Takahashi2015 : public SPH::ViscosityBase

This class implements a variant of the implicit simulation method for viscous fluids introduced by Takahashi et al. [TDF+15]. In the original work of Takahashi et al. the second-ring neighbors are required to create the matrix of the linear system. In contrast we use a meshless conjugate gradient solver which performs the required matrix-vector multiplication in two sequential loops. In this way only the one-ring neighbors are required in each loop which increases the performance significantly.

Thanks to Anreas Peer who helped us with the implementation.

References:

  • [TDF+15] T. Takahashi, Y. Dobashi, I. Fujishiro, T. Nishita, and M.C. Lin. Implicit Formulation for SPH-based Viscous Fluids. Computer Graphics Forum, 34(2):493-502, 2015. URL: http://dx.doi.org/10.1111/cgf.12578

Public Functions

Viscosity_Takahashi2015(FluidModel *model)
virtual ~Viscosity_Takahashi2015(void)
virtual void step()
virtual void reset()
virtual void performNeighborhoodSearchSort()
inline FORCE_INLINE const Matrix3r & getViscousStress (const unsigned int i) const
inline FORCE_INLINE Matrix3r & getViscousStress (const unsigned int i)
inline FORCE_INLINE void setViscousStress (const unsigned int i, const Matrix3r &val)
inline FORCE_INLINE const Vector3r & getAccel (const unsigned int i) const
inline FORCE_INLINE Vector3r & getAccel (const unsigned int i)
inline FORCE_INLINE void setAccel (const unsigned int i, const Vector3r &val)

Public Static Functions

static inline NonPressureForceBase *creator(FluidModel *model)
static void matrixVecProd(const Real *vec, Real *result, void *userData)
static FORCE_INLINE void diagonalMatrixElement (const unsigned int row, Real &result, void *userData)

Public Static Attributes

static int ITERATIONS = -1
static int MAX_ITERATIONS = -1
static int MAX_ERROR = -1

Protected Types

typedef Eigen::ConjugateGradient<MatrixReplacement, Eigen::Lower | Eigen::Upper, Eigen::IdentityPreconditioner> Solver

Protected Functions

virtual void initParameters()

Protected Attributes

std::vector<Vector3r> m_accel
std::vector<Matrix3r> m_viscousStress
Solver m_solver
unsigned int m_iterations
unsigned int m_maxIter
Real m_maxError

Protected Static Functions

static void computeViscosityAcceleration(Viscosity_Takahashi2015 *visco, const Real *v)