Stress and temperature relaxation towards equilibrium with reactions: "reactive"

Files

hetmixreac.h C++ source

Reaction model

The reactant is consumed at constant density. At any instant of time, the products will not necessarily be at the same density as the reactant because of their different compressibility. The mass reacted, its energy and the change in volume fraction are taken into account in calculating the change in product density and specific internal energy.

The reaction rate is `local' in the sense that it applies to each element of unreacted material. The reaction rate for the component as a whole is obtained by multiplying the local rate by the volume fraction of that component.

Equilibration method

As for hetmixrelax.

Input

As for hetmixrelax, followed by:

number_of_reactions
For each:
   reaction_rate
   reactant_name
   reactant_reference_specific_internal_energy
   product_name
   product_reference_state
   number_of_states_in_product_compression_reference_curve
   For each:
      density specific_internal_energy state
   specific_energy_released_in_reaction
maximum_mass_fraction_change_per_call (e.g. 0.3)
maximum_mass_fraction_change_per_subcycle (e.g. 0.1)

Notes:

The energies and reference state allow the heat of reaction to be calculated for arbitrary states of compression and heating. A reference state is chosen for the reaction (e.g. STP) and the energies and reference product state are calculated for the reference state. (This allows enthalpies of formation to be used, with suitable scaling into the units used in the calculation.) When reaction occurs at other pressures or temperatures, the corresponding state of the reactants is used to calculate the specific internal energy. The difference between this value and the reference energy is added to the specific energy release, and applied to the reference product state (mixed with any other products already present) as heat.