This optional block is placed before all RxnProcess and RxnPhysics blocks and sets the order the reactions are carried out and how frequently the reaction is updated by VSim. If this block is not included, the default values (indicated below) will be used.
updateOrder (string, optional, default = random)Sets the order in which the reactions will be carried out at each timestep.
RxnProcess Blocks in the .in file.updatePeriod (vector of integers, required, default: vector of 1's)This will set the interval (in timesteps) at which each
interaction is updated. At the indicated interval,
the reaction will be performed assuming all particles
currently in each cell were in the cell since the previous
update, using the entire time period since the previous update
to determine the reaction probability as to ensure the total number
of particle interactions remains constant regardless of
the value chosen for the updatePeriod.
Advanced users may want to manually set this parameter when running simulations which have a low reaction rate compared to the timestep (due to a small PPC, low cross-section, etc); in such cases a lower sampling rate for a reaction process may be desired. Increasing the update period will result in a small performance boost.
Each position in the vector
will match with the position of a RxnProcess Block
in a .pre file.
The RxnProcessSettings block below comes from a
simulation with 5 RxnProcess blocks. The interaction
setup in the first, third, and fifth blocks will be carried out every
timestep. The process set up in the second RxnProcess block
will be performed every 5th timestep, and the interaction
in the fourth block will be carried out every tenth timestep.
<RxnProcessSettings RxnProcessSettings>
updateOrder = random
updatePeriod = [ 1 5 1 10 1]
</RxnProcessSettings>