Subgrid Spark Ignition Models Reference

When the Laminar Flame Speed Closure (LFC) or Eddy Dissipation Concept (EDC) combustion models are active, the name of the spark model is Subgrid Spark Flame Speed Ignition, and the Laminar Flame Speed (LFS) model is selected within the spark model. For other combustion models, where LFS is specified elsewhere, the spark model name is Subgrid Spark Ignition.

Table 1. Spark Ignition Model Reference
Theory	See Ignitors.
Provided By	[physics continuum] > Models > Spark Ignition Models
Example Node Path	Continua > Physics 1 > Models > Spark Ignition
Requires	Material: Multi-Component Gas Time: any unsteady Reaction Regime: Reacting Then either of:
	Reacting Flow Models: Flamelet Flamelet Models: Flamelet Generated Manifold (FGM)	Reacting Flow Models: Reacting Species Transport Reacting Species Models: Complex Chemistry

Subgrid Spark Flame Speed Ignition Model

Table 2. Subgrid Spark Flame Speed Ignition Model Reference
Provided By	[physics continuum] > Models > Spark Ignition Models
Example Node Path	Continua > Physics 1 > Models > Subgrid Spark Flame Speed Ignition
Requires	Optional Models: Spark Ignition
Properties	Laminar Flame Speed
Ignitors	Subgrid Spark Ignitor.

Laminar Flame Speed

Method

Provides options for modeling laminar flame speed.

Method	Corresponding Method Node
Flamelet Table Laminar Flame Speed Available when the FGM model is used and the Reactor Type is set to 1D Premixed Freely Propagating.	Uses the laminar flame speed that is stored in the flamelet table generated by the FGM Table Generator. See FGM Table. Activates the Flamelet Table Laminar Flame Speed node.
Gulder Laminar Flame Speed See, Gulder.	Gulder Laminar Flame Speed Allows you to set the Fuel Name.
Metghalchi Laminar Flame Speed See Metghalchi.	Metghalchi Laminar Flame Speed Allows you to set the Fuel Name.
Universal Laminar Flame Speed Available for the Flamelet Generated Manifold model only.	Simcenter STAR-CCM+ identifies the best laminar flame speed correlation for each individual fuel in a mixture of fuels and then uses the Hirasawa method to calculate the laminar flame speed of the blended mixture of fuels that are specified Eqn. (3571). Hydrocarbons, alcohols, hydrogen and ammonia are considered as fuels. Activates the Universal Laminar Flame Speed node.
Precomputed LFS Table Available for the Complex Chemistry model only.	Uses values taken from the Laminar Flame Speed Table that is specified under the Table Generators > LFS Table Generator node. Activates the Precomputed LFS Table node which allows you to select the Laminar Flame Speed Table defined in LFS Table Generator.
User Defined Laminar Flame Speed Uses a standard scalar profile to provide the laminar flame speed.	Allows you to provide the laminar flame speed.

Flame Speed Multiplier

Available for all Laminar Flame Speed (LFS) methods.

Allows you to multiply the LFS with a scale factor. The flame speed multiplier is applied to

S_{l}

obtained from any of the LFS methods in Flame Speed Calculations.

Increasing the multiplier will increase the LFS and therefore the Turbulent Flame Speed. The recommended value ranges from 0.5 to 2. The default of 1 indicates that no multiplier is applied.

Subgrid Spark Ignition Model

Table 3. Subgrid Spark Ignition Model Reference
Provided By	[physics continuum] > Models > Optional Models
Example Node Path	Continua > Physics 1 > Models > Spark Ignition
Requires	Optional Models: Spark Ignition
Properties	Periodic Spark Ignition

Periodic Spark Ignition: When activated, provides the Periodic Spark Ignition sub-node which allows you to specify the Spark Ignition Period. The spark is ignited periodically after the specified Spark Ignition Period.

Subgrid Spark Ignitor

When the Spark Ignition model is selected as a physics model, you can create a Subgrid Spark Ignitor using the right-click option of the [Continuum] > Ignitors node.

Spark Start Time: Time from which the spark is activated, $t_{s p a r k}$ in Eqn. (3960).
Spark Position: Coordinates of the flame kernel (spark).
Coordinate System: The coordinate system which is used to define the coordinates of the spark and flame kernel location.
Turbulent Flame Speed Coefficient A: Coefficient for the turbulent flame speed, $A$ .
Maximum Duration Time: Maximum time for which the spark remains activated.
Curvature Correction: When activated, allows Simcenter STAR-CCM+ to make corrections to the flame speed due to the curvature of the kernel.
Flame Kernel Convection: When activated, Simcenter STAR-CCM+ transports the spark from the spark plug by convection.