FreeFOAM The Cross-Platform CFD Toolkit
APIdiffCoefFunc.H
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23 
24 Class
25  Foam::APIdiffCoefFunc
26 
27 Description
28  API function for vapour mass diffusivity
29 
30  Source:
31  @verbatim
32  API (American Petroleum Institute)
33  Technical Data Book
34  @endverbatim
35 
36 \*---------------------------------------------------------------------------*/
37 
38 #ifndef APIdiffCoefFunc_H
39 #define APIdiffCoefFunc_H
40 
42 
43 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
44 
45 namespace Foam
46 {
47 
48 /*---------------------------------------------------------------------------*\
49  Class APIdiffCoefFunc Declaration
50 \*---------------------------------------------------------------------------*/
51 
53 :
55 {
56  // Private data
57 
58  // API vapour mass diffusivity function coefficients
59  scalar a_, b_, wf_, wa_;
60 
61  // Helper variables
62  scalar alpha_, beta_;
63 
64 
65 public:
66 
67  //- Runtime type information
68  TypeName("APIdiffCoefFunc");
69 
70 
71  // Constructors
72 
73  //- Construct from components
74  APIdiffCoefFunc(scalar a, scalar b, scalar wf, scalar wa)
75  :
76  a_(a),
77  b_(b),
78  wf_(wf),
79  wa_(wa),
80  alpha_(sqrt(1/wf_ + 1/wa_)),
81  beta_(sqr(cbrt(a_) + cbrt(b_)))
82  {}
83 
84  //- Construct from Istream
86  :
87  a_(readScalar(is)),
88  b_(readScalar(is)),
89  wf_(readScalar(is)),
90  wa_(readScalar(is)),
91  alpha_(sqrt(1/wf_ + 1/wa_)),
92  beta_(sqr((cbrt(a_) + cbrt(b_))))
93  {}
94 
95 
96  // Member Functions
97 
98  //- API vapour mass diffusivity function using properties from
99  // construction
100  scalar f(scalar p, scalar T) const
101  {
102  return 3.6059e-3*(pow(1.8*T, 1.75))*alpha_/(p*beta_);
103  }
104 
105  //- API vapour mass diffusivity function using properties from
106  // construction - with specified binary pair
107  scalar f(scalar p, scalar T, scalar Wa) const
108  {
109  const scalar alphaBinary = sqrt(1/wf_ + 1/Wa);
110  return 3.6059e-3*(pow(1.8*T, 1.75))*alphaBinary/(p*beta_);
111  }
112 
113  //- Write the function coefficients
114  void writeData(Ostream& os) const
115  {
116  os << a_ << token::SPACE
117  << b_ << token::SPACE
118  << wf_ << token::SPACE
119  << wa_;
120  }
121 
122 
123  // Ostream Operator
124 
126  {
127  f.writeData(os);
128  return os;
129  }
130 };
131 
132 
133 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
134 
135 } // End namespace Foam
136 
137 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
138 
139 #endif
140 
141 // ************************ vim: set sw=4 sts=4 et: ************************ //