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| − | == Chemical kinetics ==
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| − | This chapter reports the principles that drive the computation of combustion chemistry in most CFD softwares.
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| − | * Arrhenius law
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| − | <math>\mathcal{A}_j</math> is the pre-exponential factor, <math>\mathcal{\beta}_j</math> is the temperature exponent and <math>E_{a_j}</math> the activation energy
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| − | <math>
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| − | k_j = \mathcal{A}_j T^{\mathcal{\beta}_j} \exp \left(-\frac{E_{a_j}}{R T}\right)
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| − | </math>
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| − | * Three-body reactions
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| − | In the forward direction, three-body reactions involve two species A and B as reactants and yield a single product AB. In that case, the third body M is used to stabilize the excited product AB*. On the contrary, in the reverse direction, heat provides the energy necessary to break the link between A and B.
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| − | <math>......</math>
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| − | The third body M can be any inert molecule.
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| − | * Falloff reactions
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| − | Under specific conditions, some reaction rate expressions are dependent on pressure and temperature. This is especially true for the rate associated to unimolecular/recombination fall-off reactions which increases with pressure. In such cases, if the chemical process takes place in a high or low pressure limit
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| − | * Reaction rates
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| − | The global rate of a reaction j (evolution in concentration per unit of time) varies depending on the proportion of the rates associated to the forward and backward directions.
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| − | <math>
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| − | \mathcal{Q}_j = \mathcal{Q}_{f,j} - \mathcal{Q}_{r,j}
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| − | </math>
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| − | * Production/Consumption source terms
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| − | Species <math>Y_k</math> source terms are deduced from
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| − | <math>
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| − | \dot{\omega}_k = W_k \sum_{j=1}^{N_R} \nu_{k,j} \mathcal{Q}_j
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| − | </math>
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| | == Solver to build reference trajectories == | | == Solver to build reference trajectories == |
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Latest revision as of 19:33, 7 March 2016
Solver to build reference trajectories
DRGEP solver for species reduction
- Compute species direct inter-relations
- Compute species relations through indirect paths
- Compute relations between targets and
DRGEP solver for reactions reduction
QSS solver
Get Gibbs Free Energy
Get Equilibrium constants
