C7+ Characterization
This section will be utilizing examples from the projects specified in this section. Make sure to add these projects first, if you want to follow along with the examples.
EOS Type and Molecular Weight Model
What would we recommend if this is your first time?
Since the choice of EOS model type shouldn't impact the final predictions, we recommend sticking with the default choice.
If you have a limited number of samples, we recommend using the molecular weights from the correlation instead of the gamma model values. We also don't recommend using LMW regression options, unless you have a large range of average molecular weights for your flashed oil fluids!
If you want to see the impact of the choice of molecular weight correlation, we suggest saving one case with both correlation types.
There are two EOS models that are avaialble in whitsonPVT when developing a new fluid model. These are the Peng-Robinson (PR) and Soave-Relich-Kwong (SRK) models. There is no fundamental or significant difference in the ability of these two models to predict hydrocarbon phase behavior, so the choice between these two models is one of preference.
The choice of molecular weight model is between using the gamma model or correlation based single carbon number (SCN) component molecular weights for your C7+ components.
The choice of molecular weight correlation is between the Effective Paraffin model and the Twu model. Even if the gamma model is chosen to use for estimating the component molecular weights, the correlation type is still used to initialize the lower molecular weights in the gamma model. If lower molecular weight tuning is applied and the gamma model molecular weights are chosen to use for the component molecular weights, the choice of correlation is not important!
Gamma Model
Example 1 - Sample CL-63169 (Duvernay) - Single Gas Sample
Example 2 - Sample CL-70055 (Duvernay) - Single Oil Sample
Example 3 - Field-Wide Fluid Model (Volve Field)
Example 4 - Basin-Wide Fluid Model (Duvernay Basin)
Specific Gravity Model
Example 1 - Sample CL-63169 (Duvernay) - Single Gas Sample
Example 2 - Sample CL-70055 (Duvernay) - Single Oil Sample
Example 3 - Field-Wide Fluid Model (Volve Field)
Example 4 - Basin-Wide Fluid Model (Duvernay Basin)
Results and Saved Cases
Next Steps
The next step in the fluid model development is to tune the initial characterized EOS model!