Vitesse_relative_base.h

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#ifndef Vitesse_relative_base_included
#define Vitesse_relative_base_included
 
#include <Correlation_base.h>
#include <TRUSTTab.h>
 
/*! @brief Relative velocity correlations of the form ur = (v_k - v_l).
 *
 *
 */
 
class Vitesse_relative_base : public Correlation_base
{
  Declare_base(Vitesse_relative_base);
 
public:
  struct input_t
  {
    double dh = 0.0;       // hydraulic diameter
    DoubleTab sigma; // surface tension sigma(ind_trav), ind_trav = (n*(N-1)-(n-1)*(n)/2) + (m-n-1)
    DoubleTab alpha; // void fraction
    DoubleTab rho;   // density
    DoubleTab mu;    // viscosity
    DoubleTab d_bulles;   // bubble diameter
    DoubleTab k;     // turbulent kinetic energy
    DoubleTab nut;   // turbulent viscosity
    DoubleTab v;     // v(n, d) : velocity of phase n in direction d
    DoubleTab gradAlpha;// gradAlpha(n,d) : gradient of void fraction; computed only if required by the correlation
    DoubleTab vort;  // vort(n,d) : vorticity; computed only if required by the correlation
    DoubleVect g;    // gravity vector
  };
  /* output values */
  struct output_t
  {
    DoubleTab vr; // vr(n, m, d) : relative velocity of phases n and m in direction d (v(n, d) - v(m, d))
    DoubleTab dvr;//dvr(n, m, d, D*l+d2) : derivative of the relative velocity of phases n and m in direction d (v(n, d) - v(m, d))
    // with respect to the velocity of phase l in direction d2
  };
  virtual void vitesse_relative(const input_t& input, output_t& output) const = 0;
  virtual bool needs_grad_alpha() const {return 0;};
  virtual bool needs_vort() const {return 0;};
  virtual void set_param(Param& param) const override { /* do nothing */ }
 
protected:
  int n_l = -1, n_g = -1; // treated phases: liquid / continuous gas
};
 
#endif /* Vitesse_relative_base_included */