Unchained flux limiters + fast recycling

include/neutral_mixed.hxx

@@ -43,13 +43,21 @@ private:
 
   Field3D Dnn; ///< Diffusion coefficient
   Field3D DnnNn, DnnPn, DnnTn, DnnNVn; ///< Used for operators
+  Field3D eta_n; ///< Viscosity
+  Field3D kappa_n; ///< Thermal conductivity
 
   bool sheath_ydown, sheath_yup;
 
   BoutReal nn_floor; ///< Minimum Nn used when dividing NVn by Nn to get Vn.
 
-  BoutReal flux_limit; ///< Diffusive flux limit
-  BoutReal diffusion_limit;    ///< Maximum diffusion coefficient
+  bool flux_limit; ///< Impose flux limiter?
+  bool particle_flux_limiter, heat_flux_limiter, momentum_flux_limiter; ///< Which limiters to impose
+  BoutReal maximum_mfp; ///< Maximum mean free path for diffusion. 0.1 by default, -1 is off.
+  BoutReal flux_limit_alpha, conductive_flux_limit_alpha, convective_flux_limit_alpha;
+  BoutReal flux_limit_gamma;
+  Field3D particle_flux_factor; ///< Particle flux scaling factor
+  Field3D momentum_flux_factor;
+  Field3D conductive_heat_flux_factor, convective_heat_flux_factor;
 
   bool neutral_viscosity; ///< include viscosity?
 

include/recycling.hxx

@@ -48,6 +48,8 @@ private:
     /// Combination of recycling fraction and species change e.g h+ -> h2 results in 0.5 multiplier
     BoutReal target_multiplier, sol_multiplier, pfr_multiplier, pump_multiplier; 
     BoutReal target_energy, sol_energy, pfr_energy; ///< Energy of recycled particle (normalised to Tnorm)
+    BoutReal target_fast_recycle_fraction, pfr_fast_recycle_fraction, sol_fast_recycle_fraction;   ///< Fraction of ions undergoing fast reflection
+    BoutReal target_fast_recycle_energy_factor, sol_fast_recycle_energy_factor, pfr_fast_recycle_energy_factor;   ///< Fraction of energy retained by fast recycled neutrals
   };
 
   std::vector<RecycleChannel> channels; // Recycling channels
@@ -56,16 +58,17 @@ private:
   bool diagnose; ///< Save additional post-processing variables?
 
   Field3D density_source, energy_source; ///< Recycling particle and energy sources for all locations
-  Field2D is_pump; ///< 1 = pump, 0 = no pump. Works only in SOL/PFR
+  Field3D energy_flow_ylow, energy_flow_xlow; ///< Cell edge fluxes used for calculating fast recycling energy source
+  Field3D particle_flow_xlow; ///< Radial wall particle fluxes for recycling calc. No need to get poloidal from here, it's calculated from sheath velocity
+
+  Field2D is_pump; ///< 1 = pump, 0 = no pump. Works only in SOL/PFR. Provided by user in grid file.
 
   // Recycling particle and energy sources for the different sources of recycling
   // Note that SOL, PFR and pump are not applicable to 1D
   Field3D target_recycle_density_source, target_recycle_energy_source; 
   Field3D wall_recycle_density_source, wall_recycle_energy_source;  ///< Recycling particle and energy sources for pfr + sol recycling
-  Field3D pump_recycle_density_source, pump_recycle_energy_source; 
+  Field3D pump_density_source, pump_energy_source;  ///< Recycling particle and energy sources for pump recycling
 
-  Field3D radial_particle_outflow, radial_energy_outflow;  ///< Radial fluxes coming from evolve_density and evolve_pressure used in recycling calc
-
 };
 
 namespace {