- Saturations, phase pressures, and standard initialsation of RS and RV
now agree to baseline.
- Tables of RS and RV versus vertical depth (kw RSVD RVVD) have been
hardcoded for testing (need new parser) and the calculations agree to
baseline in the gas and oil zones. In the water zone there is some
differences: Our code computes saturated RS and RV using the final
phase pressures (these are modified to be consistent with saturations
and capillary pressures) while the baseline uses unmodified phase pressures.
Instead of making well rates zero for wells that are not controlled by
surface volume, we initialize them to a small value with the correct
sign (positive for injectors, negative for producers).
It is not quite complete yet for the following reasons:
- it does not compute state.surfacevol(),
- the InitialStateComputer class does not compute Rs or Rv,
- it has not been verified.
In summary:
- added RsFunction (base class),
- made NoMixing, RsVD, RsSatAtContact inherit RsFunction,
- RS and RV are no longer template arguments for EquilReg class,
- EquilReg constructor now takes two shared_ptr<Miscibility::RsFunction>,
- use of constructor updated, mostly using make_shared.
The initial implementation of RK4IVP<>::operator() failed to take
into account the possibility that we might need to evaluate the
function outside the vertical span for which it was initially
defined. This situation occurs, for instance, in the not uncommon
cases of the GOC being above or the WOC being below the model.
This commit installs a crude Hermitian extrapolation procedure to
handle these cases. Refinements are likely.
This commit adds support for assigning the initial phase pressure
distribution to a subset of the total grid cells. This is needed in
order to fully support equilibration regions. The existing region
support (template parameter 'Region' in function 'phasePressures()')
was only used/needed to define PVT property (specifically, the fluid
phase density) calculator pertaining to a particular equilibration
region.
This commit adds a simple facility for calculating initial phase
pressures assuming stationary conditions, a known reference pressure
in the oil zone as well as the depth and capillary pressures at the
water-oil and gas-oil contacts.
Function 'Opm::equil::phasePressures()' uses a simple ODE/IVP-based
approach, solved using the traditional RK4 method with constant step
sizes, to derive the required pressure values. Specifically, we
solve the ODE
dp/dz = rho(z,p) * g
with 'z' represening depth, 'p' being a phase pressure and 'rho' the
associate phase density. Finally, 'g' is the acceleration of
gravity. We assume that we can calculate phase densities, e.g.,
from table look-up. This assumption holds in the case of an ECLIPSE
input deck.
Using RK4 with constant step sizes is a limitation of this
implementation. This, basically, assumes that the phase densities
varies only smoothly with depth and pressure (at reservoir
conditions).
The pvt interface is extended to handle wet-gas systems:
1. rvSat is added as a function in the PVT interface
2. SinglePvtLiveGas computes the pvt values and its derivatives
3. The old rbub variable is changed to rsSat for clearity
4. The new interface is tested in test_blackoilfluid with data from
liveoil.DATA and wetgas.DATA
