effectivenessHeatExchangerSource.H
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23 
24 Class
25  Foam::fv::effectivenessHeatExchangerSource
26 
27 Description
28  Heat exchanger source model, in which the heat exchanger is defined as a
29  selection of cells.
30 
31  The total heat exchange source is given by:
32  \f[
33  Q_t = e(\phi, \dot{m}_2) (T_2 - T_1) \phi c_p
34  \f]
35 
36  where:
37  \vartable
38  Q_t | total heat source
39  e(\phi,\dot{m}_2) | effectivenes table
40  \phi | net mass flux entering heat exchanger [kg/s]
41  \dot{m}_2 | secondary mass flow rate [kg/s]
42  T_1 | primary inlet temperature [K]
43  T_2 | secondary inlet temperature [K]
44  c_p | specific heat capacity [J/kg/K]
45  \endvartable
46 
47 
48  The distribution inside the hear exchanger is given by:
49  \f[
50  Q_c = \frac{V_c |U_c| (T_c - T_{ref})}{\sum(V_c |U_c| (T_c - T_{ref}))}
51  \f]
52 
53  where:
54  \vartable
55  Q_c | source for cell
56  V_c | volume of the cell [m3]
57  U_c | local cell velocity [m/s]
58  T_c | local call temperature [K]
59  T_{ref} | min or max(T) in cell zone depending on the sign of Q_t [K]
60  \endvartable
61 
62 Usage
63  Example usage:
64  \verbatim
65  effectivenessHeatExchangerSource1
66  {
67  type effectivenessHeatExchangerSource;
68  active yes;
69 
70  selectionMode cellZone;
71  cellZone porosity;
72 
73  secondaryMassFlowRate 1.0;
74  secondaryInletT 336;
75  primaryInletT 293;
76  faceZone facesZoneInletOriented;
77  outOfBounds clamp;
78  file "effTable";
79  }
80  \endverbatim
81 
82  The effectiveness table is described in terms of the primary and secondary
83  mass flow rates. For example, the table:
84 
85  secondary MFR
86  | 0.1 0.2 0.3
87  -----+-----------------
88  0.02 | A B C
89  primary MFR 0.04 | D E F
90  0.06 | G H I
91 
92 
93  Is specified by the following:
94 
95  (
96  0.02
97  (
98  (0.1 A)
99  (0.2 B)
100  (0.3 C)
101  ),
102  0.04
103  (
104  (0.1 D)
105  (0.2 E)
106  (0.3 F)
107  ),
108  0.06
109  (
110  (0.1 G)
111  (0.2 H)
112  (0.3 I)
113  )
114  );
115 
116 
117 Note
118 - the table with name "file" should have the same units as the
119  secondary mass flow rate and kg/s for phi
120 - faceZone is the faces at the inlet of the cellzone, it needs to be
121  created with flip map flags. It is used to integrate the net mass flow
122  rate into the heat exchanger
123 
124 
125 SourceFiles
126  effectivenessHeatExchangerSource.C
127 
128 \*---------------------------------------------------------------------------*/
129 
130 #ifndef effectivenessHeatExchangerSource_H
131 #define effectivenessHeatExchangerSource_H
132 
133 #include "cellSetOption.H"
134 #include "autoPtr.H"
135 #include "interpolation2DTable.H"
136 
137 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
138 
139 namespace Foam
140 {
141 namespace fv
142 {
143 
144 /*---------------------------------------------------------------------------*\
145  Class effectivenessHeatExchangerSource Declaration
146 \*---------------------------------------------------------------------------*/
147 
148 class effectivenessHeatExchangerSource
149 :
150  public cellSetOption
151 {
152 
153 protected:
154 
155  // Protected data
156 
157  //- Secondary flow mass rate [kg/s]
158  scalar secondaryMassFlowRate_;
159 
160  //- Inlet secondary temperature [K]
161  scalar secondaryInletT_;
162 
163  //- Primary air temperature at the heat exchanger inlet [K]
164  scalar primaryInletT_;
165 
166  //- 2D look up table efficiency = function of primary and secondary
167  // mass flow rates [kg/s]
168  autoPtr<interpolation2DTable<scalar>> eTable_;
169 
170  //- Name of velocity field; default = U
171  word UName_;
172 
173  //- Name of temperature field; default = T
174  word TName_;
175 
176  //- Name of the flux
177  word phiName_;
178 
179  //- Name of the faceZone at the heat exchange inlet
180  word faceZoneName_;
181 
182  //- Id for the face zone
183  label zoneID_;
184 
185  //- Local list of face IDs
187 
188  //- Local list of patch ID per face
190 
191  //- List of +1/-1 representing face flip map (1 use as is, -1 negate)
193 
194  //- Area of the face zone
196 
197 
198 private:
199 
200  // Private Member Functions
201 
202  //- Disallow default bitwise copy construct
204  (
206  );
207 
208  //- Disallow default bitwise assignment
209  void operator=(const effectivenessHeatExchangerSource&);
210 
211  //- Initialise heat exchanger source model
212  void initialise();
213 
214  //- Calculate total area of faceZone across processors
215  void calculateTotalArea(scalar& area);
216 
217 
218 public:
219 
220  //- Runtime type information
221  TypeName("effectivenessHeatExchangerSource");
222 
223 
224  // Constructors
225 
226  //- Construct from components
228  (
229  const word& name,
230  const word& modelType,
231  const dictionary& dict,
232  const fvMesh& mesh
233  );
234 
235 
236  //- Destructor
238  {}
240 
241  // Member Functions
243  // Explicit and implicit source
244 
245  //- Scalar
246  virtual void addSup
247  (
248  fvMatrix<scalar>& eqn,
249  const label fieldi
250  )
251  {
253  }
254 
255 
256  // Explicit and implicit source for compressible equation
257 
258  //- Scalar
259  virtual void addSup
260  (
261  const volScalarField& rho,
262  fvMatrix<scalar>& eqn,
263  const label fieldi
264  );
265 
266 
267  // IO
268 
269  //- Read dictionary
270  virtual bool read(const dictionary& dict);
271 };
272 
273 
274 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
275 
276 } // End namespace fv
277 } // End namespace Foam
278 
279 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
280 
281 #endif
282 
283 // ************************************************************************* //
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
scalar secondaryInletT_
Inlet secondary temperature [K].
A list of keyword definitions, which are a keyword followed by any number of values (e...
Definition: dictionary.H:137
virtual bool read(const dictionary &dict)
Read dictionary.
word TName_
Name of temperature field; default = T.
word faceZoneName_
Name of the faceZone at the heat exchange inlet.
const fvMesh & mesh() const
Return const access to the mesh database.
Definition: fvOptionI.H:34
A class for handling words, derived from string.
Definition: word.H:59
labelList fv(nPoints)
scalar primaryInletT_
Primary air temperature at the heat exchanger inlet [K].
A special matrix type and solver, designed for finite volume solutions of scalar equations. Face addressing is used to make all matrix assembly and solution loops vectorise.
Definition: fvPatchField.H:72
List< label > labelList
A List of labels.
Definition: labelList.H:56
const word & name() const
Return const access to the source name.
Definition: fvOptionI.H:28
TypeName("effectivenessHeatExchangerSource")
Runtime type information.
Heat exchanger source model, in which the heat exchanger is defined as a selection of cells...
Mesh data needed to do the Finite Volume discretisation.
Definition: fvMesh.H:78
labelList faceSign_
List of +1/-1 representing face flip map (1 use as is, -1 negate)
autoPtr< interpolation2DTable< scalar > > eTable_
2D look up table efficiency = function of primary and secondary
labelList facePatchId_
Local list of patch ID per face.
scalar secondaryMassFlowRate_
Secondary flow mass rate [kg/s].
#define NotImplemented
Issue a FatalErrorIn for a function not currently implemented.
Definition: error.H:366
word UName_
Name of velocity field; default = U.
virtual void addSup(fvMatrix< scalar > &eqn, const label fieldi)
Scalar.
Namespace for OpenFOAM.