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LehrMilliesMewesCoalescence.H
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23 
24 Class
25  Foam::diameterModels::coalescenceModels::LehrMilliesMewesCoalescence
26 
27 Description
28  Model of Lehr et al. (2002). The coalescence rate is calculated by
29 
30  \f[
31  \frac{\pi}{4} (d_i + d_j)^2 \mathrm{min}(u^{\prime}, u_{\mathrm{crit}})
32  \mathrm{exp}
33  \left[
34  - \left(\frac{\alpha_{\mathrm{max}}^{1/3}}{\alpha^{1/3}} - 1\right)^2
35  \right]\,,
36  \f]
37 
38  where
39 
40  \f[
41  u^{\prime}
42  =
43  \mathrm{max}
44  \left(
45  \sqrt{2} \epsilon_c^{1/3} \sqrt{d_i^{2/3} + d_j^{2/3}},
46  |\vec{u}_i - \vec{u}_j|
47  \right)
48  \f]
49 
50  is the characteristic velocity for coalescence. Note that a velocity
51  difference between bubble i and j is only present if the corresponding
52  size groups are assigned to different velocity groups.
53 
54  \vartable
55  d_i | Diameter of bubble i [m]
56  d_j | Diameter of bubble j [m]
57  \epsilon_c | Turbulent dissipation rate of continuous phase [m^2/s^3]
58  \alpha | Total void fraction of the bubbles [-]
59  \alpha_{max} | Maximum packing density of the bubbles [-]
60  u_{crit} | Critical velocity for coalescence [m/s]
61  \vec{u}_i | Velocity vector of bubble i [m/s]
62  \vec{u}_j | Velocity vector of bubble j [m/s]
63  \endvartable
64 
65  Reference:
66  \verbatim
67  Lehr, F., Millies, M., & Mewes, D. (2002).
68  Bubble‐size distributions and flow fields in bubble columns.
69  AIChE Journal, 48(11), 2426-2443.
70  \endverbatim
71 
72 Usage
73  \table
74  Property | Description | Required | Default value
75  uCrit | Crit. coalescence velocity | no | 0.08
76  alphaMax | Maximum packing density | no | 0.6
77  \endtable
78 
79 SourceFiles
80  LehrMilliesMewesCoalescence.C
81 
82 \*---------------------------------------------------------------------------*/
83 
84 #ifndef LehrMilliesMewesCoalescence_H
85 #define LehrMilliesMewesCoalescence_H
86 
87 #include "coalescenceModel.H"
88 
89 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
90 
91 namespace Foam
92 {
93 namespace diameterModels
94 {
95 namespace coalescenceModels
96 {
97 
98 /*---------------------------------------------------------------------------*\
99  Class LehrMilliesMewesCoalescence Declaration
100 \*---------------------------------------------------------------------------*/
101 
102 class LehrMilliesMewesCoalescence
103 :
104  public coalescenceModel
105 {
106  // Private Data
107 
108  //- Critical velocity for coalescence, defaults to 0.08 m/s
109  dimensionedScalar uCrit_;
110 
111  //- Maximum packing density of the bubbles, defaults to 0.6
112  dimensionedScalar alphaMax_;
113 
114 
115 public:
116 
117  //- Runtime type information
118  TypeName("LehrMilliesMewes");
119 
120  // Constructor
121 
123  (
124  const populationBalanceModel& popBal,
125  const dictionary& dict
126  );
127 
128 
129  //- Destructor
131  {}
132 
133 
134  // Member Functions
135 
136  //- Add to coalescenceRate
137  virtual void addToCoalescenceRate
138  (
139  volScalarField& coalescenceRate,
140  const label i,
141  const label j
142  );
143 };
144 
145 
146 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
147 
148 } // End namespace coalescenceModels
149 } // End namespace diameterModels
150 } // End namespace Foam
151 
152 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
153 
154 #endif
155 
156 // ************************************************************************* //
dictionary dict
intWM_LABEL_SIZE_t label
A label is an int32_t or int64_t as specified by the pre-processor macro WM_LABEL_SIZE.
Definition: label.H:59
virtual void addToCoalescenceRate(volScalarField &coalescenceRate, const label i, const label j)
Add to coalescenceRate.
GeometricField< scalar, fvPatchField, volMesh > volScalarField
Definition: volFieldsFwd.H:57
LehrMilliesMewesCoalescence(const populationBalanceModel &popBal, const dictionary &dict)
dimensioned< scalar > dimensionedScalar
Dimensioned scalar obtained from generic dimensioned type.
TypeName("LehrMilliesMewes")
Runtime type information.
Namespace for OpenFOAM.