Model of Lehr et al. (2002). The coalescence rate is calculated by. More...
Public Member Functions | |
| TypeName ("LehrMilliesMewes") | |
| Runtime type information. More... | |
| LehrMilliesMewesCoalescence (const populationBalanceModel &popBal, const dictionary &dict) | |
| virtual | ~LehrMilliesMewesCoalescence ()=default |
| Destructor. More... | |
| virtual void | addToCoalescenceRate (volScalarField &coalescenceRate, const label i, const label j) |
| Add to coalescenceRate. More... | |
Public Member Functions inherited from coalescenceModel | |
| TypeName ("coalescenceModel") | |
| Runtime type information. More... | |
| declareRunTimeSelectionTable (autoPtr, coalescenceModel, dictionary,(const populationBalanceModel &popBal, const dictionary &dict),(popBal, dict)) | |
| coalescenceModel (const populationBalanceModel &popBal, const dictionary &dict) | |
| autoPtr< coalescenceModel > | clone () const |
| virtual | ~coalescenceModel ()=default |
| Destructor. More... | |
| virtual void | correct () |
| Correct diameter independent expressions. More... | |
Additional Inherited Members | |
Static Public Member Functions inherited from coalescenceModel | |
| static autoPtr< coalescenceModel > | New (const word &type, const populationBalanceModel &popBal, const dictionary &dict) |
Protected Attributes inherited from coalescenceModel | |
| const populationBalanceModel & | popBal_ |
| Reference to the populationBalanceModel. More... | |
Model of Lehr et al. (2002). The coalescence rate is calculated by.
\[ \frac{\pi}{4} (d_i + d_j)^2 \mathrm{min}(u^{\prime}, u_{\mathrm{crit}}) \mathrm{exp} \left[ - \left(\frac{\alpha_{\mathrm{max}}^{1/3}}{\alpha^{1/3}} - 1\right)^2 \right]\,, \]
where
\[ u^{\prime} = \mathrm{max} \left( \sqrt{2} \epsilon_c^{1/3} \sqrt{d_i^{2/3} + d_j^{2/3}}, |\vec{u}_i - \vec{u}_j| \right) \]
is the characteristic velocity for coalescence. Note that a velocity difference between bubble i and j is only present if the corresponding size groups are assigned to different velocity groups.
| \( d_i \) | = | Diameter of bubble i [m] |
| \( d_j \) | = | Diameter of bubble j [m] |
| \( \epsilon_c \) | = | Turbulent dissipation rate of continuous phase [m2/s3] |
| \( \alpha \) | = | Total void fraction of the bubbles [-] |
| \( \alpha_{max} \) | = | Maximum packing density of the bubbles [-] |
| \( u_{crit} \) | = | Critical velocity for coalescence [m/s] |
| \( \vec{u}_i \) | = | Velocity vector of bubble i [m/s] |
| \( \vec{u}_j \) | = | Velocity vector of bubble j [m/s] |
Reference:
Lehr, F., Millies, M., & Mewes, D. (2002).
Bubbleâsize distributions and flow fields in bubble columns.
AIChE Journal, 48(11), 2426-2443.| Property | Description | Required | Default value |
|---|---|---|---|
uCrit | Crit. coalescence velocity | no | 0.08 |
alphaMax | Maximum packing density | no | 0.6 |
Definition at line 150 of file LehrMilliesMewesCoalescence.H.
| LehrMilliesMewesCoalescence | ( | const populationBalanceModel & | popBal, |
| const dictionary & | dict | ||
| ) |
Definition at line 59 of file LehrMilliesMewesCoalescence.C.
|
virtualdefault |
Destructor.
| TypeName | ( | "LehrMilliesMewes" | ) |
Runtime type information.
|
virtual |
Add to coalescenceRate.
Implements coalescenceModel.
Definition at line 81 of file LehrMilliesMewesCoalescence.C.
References Foam::cbrt(), sizeGroup::d(), Foam::exp(), Foam::mag(), Foam::max(), Foam::min(), sizeGroup::phase(), Foam::constant::mathematical::pi(), phaseModel::residualAlpha(), Foam::sqr(), Foam::sqrt(), and phaseModel::U().