Condensation

Header file: <libs/superdrops/condensation.hpp> [source]

struct DoCondensation

Implements condensation and evaporation microphysics for super-droplets.

Public Functions

inline DoCondensation(const bool do_alter_thermo, const double delt, const size_t maxniters, const double rtol, const double atol, const double minsubdelt)

Constructs a DoCondensation object.

Parameters:

  • do_alter_thermo – Whether to alter the thermodynamics of the State.

  • delt – Time step to integrate ODE using implcit Euler method.

  • maxniters – Maximum no. iterations of Newton Raphson Method.

  • rtol – Relative tolerance for implicit Euler method.

  • atol – Absolute tolerance for implicit Euler method.

  • minsubdelt – Minimum subtimestep in cases of substepping implicit Euler method.

inline void operator()(const TeamMember &team_member, const unsigned int subt, subviewd_supers supers, State &state, const SDMMonitor auto mo) const

Operator used as an “adaptor” for using condensation as the function-like type satisfying the MicrophysicsFunction concept.

This operator is an “adaptor” for using condensation as the MicrophysicsFunction type in a ConstTstepMicrophysics instance (hint which satsifies the MicrophysicalProcess concept).

Parameters:

  • team_member – The Kokkos team member.

  • subt – The microphysics time step.

  • supers – The view of super-droplets.

  • state – The State.

  • mo – Monitor of SDM processes.

Returns:

The updated view super-droplets.

Private Functions

inline void do_condensation(const TeamMember &team_member, const subviewd_supers supers, State &state, const SDMMonitor auto mo) const

Enacts condensation / evaporation microphysics.

Enacts condensation / evaporation microphysics. Change to superdroplet radius, and optionally thermodynamics of the State due to sum of water condensed via diffusion and condensation / evporation of water vapour during a given timestep delt. Using equations (eqn [X.YY]) from “An Introduction To Clouds From The Microscale to Climate” by Lohmann, Luond and Mahrt, 1st edition.

Parameters:

  • team_member – The Kokkos team member.

  • supers – The superdroplets.

  • state – The state.

  • mo – Monitor of SDM processes.

double superdroplets_change(const TeamMember &team_member, const subviewd_supers supers, const State &state) const

Changes super-droplet radii according to condensation / evaporation and returns the total change in liquid water mass in volume as a result.

returns total change in liquid water mass (dimensionless) in volume, ‘mass_condensed’, due to condensation onto / evaporation of super-droplets.

The equivalent serial version of Kokkos::parallel_reduce([…]) is summing deltamass over loop: 

for (size_t ii(0); ii < ngbxs; ++ii)
{
 [...]
 totmass_condensed += deltamass;
}

Parameters:

  • team_member – The Kokkos team member.

  • supers – The superdroplets.

  • state – The state.

Returns:

The total change in liquid water mass.

void effect_on_thermodynamic_state(const TeamMember &team_member, const double totmass_condensed, State &state) const

Applies the effect of condensation / evaporation on the thermodynamics of the State.

if do_alter_thermo is true, use a single team member to change the thermodynamics of the State due to the effect of condensation / evaporation.

Parameters:

  • team_member – The Kokkos team member.

  • totmass_condensed – The total mass of liquid condensed.

  • state – The State of the volume containing the super-droplets (prior to condensation / evaporation).

Private Members

bool do_alter_thermo

Whether to make condensation/evaporation alter State or not

ImplicitEuler impe

instance of ImplicitEuler ODE solver

inline MicrophysicalProcess auto Condensation(const unsigned int interval, const std::function<double(unsigned int)> step2dimlesstime, const bool do_alter_thermo, const size_t maxniters, const double rtol, const double atol, const double MINSUBDELT, const std::function<double(double)> realtime2dimless)

Constructs a microphysical process for condensation / evaporation of super-droplets with a constant time-step ‘interval’.

Parameters:

  • interval – The constant time-step for condensation.

  • do_alter_thermo – Whether to alter the thermodynamic state after condensation / evaporation.

  • maxniters – Maximum no. iterations of Newton Raphson Method.

  • step2dimlesstime – A function to convert ‘interval’ time-step to a dimensionless time.

  • rtol – Relative tolerance for implicit Euler method.

  • atol – Absolute tolerance for implicit Euler method.

  • MINSUBDELT – Minimum subtimestep in cases of substepping implicit Euler method.

  • realtime2dimless – A function to convert a real-time to a dimensionless time.

Returns:

The constructed microphysical process for condensation / evaporation.