Materials

Materials Right-Click Actions


Object	Right-Click Action
Materials
Air	Edit Opens a dialog that allows you to set the air composition. See Air Dialog.
Exhaust	Edit Opens a dialog that allows you to set the composition of the burnt fuel for initialization and boundary conditions. See Exhaust Dialog.
Fuel	Edit Opens a dialog that allows you to set the fuel composition. See Fuel Dialog.

Air Dialog


Air Properties
Air Component	Specifies a component of the air that passes through the engine.
Mass Weighting	Specifies the mass weighting of the specified air component in the air that passes through the engine. Simcenter STAR-CCM+ In-cylinder calculates a given material property, such as density, of the air as: Figure 1. EQUATION_DISPLAY $ϕ_{a i r} = \sum_{i = 1}^{n} {Y_{i} ϕ}_{i}$ (579) with: Figure 2. EQUATION_DISPLAY $Y_{i} = \frac{W_{i}}{\sum_{j = 1}^{n} W_{j}}$ (580) where: $W_{i}$ is the specified Mass Weighting of air component $i$ . $ϕ_{i}$ is the material property value of air component $i$ . $n$ is the total number of air components.

Exhaust Dialog


Exhaust Properties
Exhaust Component	Specifies a component of the exhaust gas. For ECFM combustion simulations, the following components are available: N2 (Nitrogen) O2 (Oxygen) CO2 (Carbon Dioxide) H2O (Water) CO (Carbon Monoxide) H2 (Hydrogen) O (O) N (N) OH (OH) H (H) C(S) (C(S)) NO (Nitric Oxide)
Mass Weighting	When Automatic Composition Initialization is On, displays the calculated mass weighting of the component in the exhaust gas. For more information, see In-cylinder Formulation—Exhaust Gas Composition When Automatic Composition Initialization is Off, allows you to specify the mass weighting. Simcenter STAR-CCM+ In-cylinder calculates a given material property, such as density, of the exhaust gas as given by Eqn. (579).

Fuel Dialog

Fuel Properties

Liquid

(if the Injection engine model is selected)

Specifies the materials of the injected liquid fuel and the vapor arising from that fuel, respectively.

Note	If the material database from which you select the liquid fuel does not provide surface tension data for that liquid, Simcenter STAR-CCM+ In-cylinder uses the surface tension of water under ambient conditions (0.072 N/m) by default.

Vapor

(if the Injection engine model is selected)

Fuel Component

(if the Injection engine model is NOT selected)

Specifies the material of the gaseous fuel.

Mass Weighting

Specifies the mass weighting $W$ of the specified fuel component.

For liquid fuel injection, specifies the mass weighting of the specified Liquid component.

Simcenter STAR-CCM+ In-cylinder calculates a given fuel property by mass-weighting the component property values as given by Eqn. (579).

Stoichiometric A/F Ratio

Displays the ideal ratio of air to the specified fuel to completely burn the fuel without excess air. See

{AFR}_{stoich}

in Solution Analysis—Plots and Solution Analysis—Scenes.

LHV (Lower Heating Value)

For single-component fuels, displays the lower heating value of the fuel according to the ECFM material database.

You can replace the default value with an experimentally determined value. To match the entry, Simcenter STAR-CCM+ In-cylinder internally adjusts a coefficient representing the fuel's heat of formation.