def __init__(
self,
surfactantVar=None,
distanceVar=None,
bulkVar=None,
rateConstant=None,
otherVar=None,
otherBulkVar=None,
otherRateConstant=None,
consumptionCoeff=None,
):
"""
Create a `AdsorbingSurfactantEquation` object.
:Parameters:
- `surfactantVar`: The `SurfactantVariable` to be solved for.
- `distanceVar`: The `DistanceVariable` that marks the interface.
- `bulkVar`: The value of the `surfactantVar` in the bulk.
- `rateConstant`: The adsorption rate of the `surfactantVar`.
- `otherVar`: Another `SurfactantVariable` with more surface affinity.
- `otherBulkVar`: The value of the `otherVar` in the bulk.
- `otherRateConstant`: The adsorption rate of the `otherVar`.
- `consumptionCoeff`: The rate that the `surfactantVar` is consumed during deposition.
"""
SurfactantEquation.__init__(self, distanceVar=distanceVar)
spCoeff = _AdsorptionCoeffInterfaceFlag(distanceVar, bulkVar, rateConstant)
scCoeff = _AdsorptionCoeffAreaOverVolume(distanceVar, bulkVar, rateConstant)
self.eq += ImplicitSourceTerm(spCoeff) - scCoeff
self.coeffs = (scCoeff, spCoeff)
if otherVar is not None:
otherSpCoeff = _AdsorptionCoeffInterfaceFlag(distanceVar, otherBulkVar, otherRateConstant)
otherScCoeff = _AdsorptionCoeffAreaOverVolume(
distanceVar, -bulkVar * otherVar.getInterfaceVar(), rateConstant
)
self.eq += ImplicitSourceTerm(otherSpCoeff) - otherScCoeff
self.coeffs += (otherScCoeff,)
self.coeffs += (otherSpCoeff,)
vars = (surfactantVar, otherVar)
else:
vars = (surfactantVar,)
spMaxCoeff = _SpMaxCoeff(distanceVar, vars)
scMaxCoeff = _ScMaxCoeff(distanceVar, vars)
self.eq += ImplicitSourceTerm(spMaxCoeff) - scMaxCoeff - 1e-40
if consumptionCoeff is not None:
self.eq += ImplicitSourceTerm(consumptionCoeff)
def solve(self, var, boundaryConditions=(), solver=LinearPCGSolver(), dt = 1.):
"""
Builds and solves the `AdsorbingSurfactantEquation`'s linear system once.
:Parameters:
- `var`: A `SurfactantVariable` to be solved for. Provides the initial condition, the old value and holds the solution on completion.
- `solver`: The iterative solver to be used to solve the linear system of equations.
- `boundaryConditions`: A tuple of boundaryConditions.
- `dt`: The time step size.
"""
for coeff in self.coeffs:
coeff._updateDt(dt)
SurfactantEquation.solve(self, var, boundaryConditions=boundaryConditions, solver=solver, dt=dt)
def sweep(self, var, solver=None, boundaryConditions=(), dt=1.0, underRelaxation=None, residualFn=None):
r"""
Builds and solves the `AdsorbingSurfactantEquation`'s linear
system once. This method also recalculates and returns the
residual as well as applying under-relaxation.
:Parameters:
- `var`: The variable to be solved for. Provides the initial condition, the old value and holds the solution on completion.
- `solver`: The iterative solver to be used to solve the linear system of equations.
- `boundaryConditions`: A tuple of boundaryConditions.
- `dt`: The time step size.
- `underRelaxation`: Usually a value between `0` and `1` or `None` in the case of no under-relaxation
"""
for coeff in self.coeffs:
coeff._updateDt(dt)
if solver is None:
solver = DefaultAsymmetricSolver()
return SurfactantEquation.sweep(
self,
var,
solver=solver,
boundaryConditions=boundaryConditions,
dt=dt,
underRelaxation=underRelaxation,
residualFn=residualFn,
)
