docs: Compositional fluid model documentation - #3713
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Co-authored-by: Jian Huang <53012159+jhuang2601@users.noreply.github.com>
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Kudos 👏 on such a delicat task of being succint but offering enough organized information to understand all implementation choice.
Few cosmetic suggestions to have homogene notations
| Immiscible water density | ||
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| A simplified exponential density model is available for pure, immiscible water phases. It evaluates the mass density, :math:`\rho`, based on isothermal compressibility and thermal expansion from a reference state: |
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| A simplified exponential density model is available for pure, immiscible water phases. It evaluates the mass density, :math:`\rho`, based on isothermal compressibility and thermal expansion from a reference state: | |
| A simplified exponential density model is available for pure, immiscible water phases. It evaluates the mass density, :math:`\rho`, based on isothermal compressibility :math:`c_w` and thermal expansion :math:`\alpha_w` from a reference state: |
| .. math:: | ||
| \frac{H_{dep}}{RT} = Z - 1 + \frac{A + T\frac{\partial A}{\partial T}}{B(\delta_1 - \delta_2)} \ln \left( \frac{Z + \delta_1 B}{Z + \delta_2 B} \right) | ||
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| where :math:`Z` is the compressibility factor of the mixture. |
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where the coefficients are defined by the dimensionless mixture parameters :math:A and :math:B: see EOS
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| For aqueous phases containing dissolved salts, cubic equations of state often struggle to capture complex ionic interactions. To address this, the Phillips brine density model utilizes the empirical correlation developed by Phillips et al. (1981) to pre-compute a 2D lookup table of volume shifts specifically for the water component as a function of pressure and temperature. | ||
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| First, the apparent molar weight of the brine, :math:`MW_{brine}`, is calculated from the salinity, :math:`S` (molality), the salt molar weight, :math:`MW_{salt}`, and the water molar weight, :math:`MW_{H2O}`: |
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should we call salt molality it m for consistent notation througout the doc or S below ?
| .. math:: | ||
| a_{i,k} = \hat{a}_{i,k} M_i | ||
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| Implementing the Michaelides Model |
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Would it be clearer to rename this section Liquid brine enthalpy IIUC
| The Peng-Robinson (PR) (Peng and Robinson, 1976; Robinson and Peng, 1978) and Soave-Redlich-Kwong (SRK) (Soave, 1972) equations of state are widely used for hydrocarbon systems encompassing natural gas, gas condensates, and volatile oils. The fundamental pressure-volume-temperature (PVT) relationships for these equations are defined as: | ||
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| * Peng-Robinson (PR): | ||
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I am wondering if a 2-col table here would not be of great visual aid
| Note on Component Limits | ||
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| When compositional fluid models are evaluated in standalone mode (for example, using the ``PVTDriver`` task (:ref:`PVTDriver`)), the maximum number of allowed components is 9. However, when these fluid models are actively coupled with a flow solver during a full simulation, the maximum number of components is restricted to 5. |
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| When compositional fluid models are evaluated in standalone mode (for example, using the ``PVTDriver`` task (:ref:`PVTDriver`)), the maximum number of allowed components is 9. However, when these fluid models are actively coupled with a flow solver during a full simulation, the maximum number of components is restricted to 5. | |
| .. warning:: | |
| When compositional fluid models are evaluated in standalone mode (for example, using the ``PVTDriver`` task (:ref:`PVTDriver`)), the maximum number of allowed components is 9. However, when these fluid models are actively coupled with a flow solver during a full simulation, the maximum number of components is restricted to 5. | |
(might miss an indent)
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| Miscellaneous | |||
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Tbf I would merge misc at the end of Overview as these infos are not to be overlooked
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| \xi_i = \frac{T_{c,i}^{1/6}}{M_i^{1/2} P_{c,i}^{2/3}} | ||
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| where :math:`T_{c,i}` is the critical temperature [K], :math:`P_{c,i}` is the critical pressure [atm], and :math:`M_i` is the molar weight [g/mol]. |
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Adds complete documentation for the compositional fluid models that have been added.