23.3.10 Point Properties for Flat-Fan Atomizer Injections

The flat-fan atomizer model is available only for 3D models. For this type of injection, you will define the following initial conditions under Point Properties:

• arc position

  Set the coordinates of the center point of the arc from which the fan originates in the X-Center, Y-Center, and Z-Center fields (see this figure in the separate Theory Guide).

• virtual position

  Set the coordinates of the virtual origin of the fan in the X-Virtual Origin, Y-Virtual Origin, and Z-Virtual Origin fields. This point is the intersection of the lines that mark the sides of the fan (see this figure in the separate Theory Guide).

• normal vector

  Set the direction that is normal to the fan in the X-Fan Normal Vector, Y-Fan Normal Vector, and Z-Fan Normal Vector fields.

• temperature

  Set the temperature of the streams in the Temperature field.

• mass flow rate

  Set the mass flow rate for the streams in the atomizer in the Flow Rate field.

• duration of injection

  For unsteady particle tracking (see Section  23.2.2), set the starting and ending time for the injection in the Start Time and Stop Time fields. When In-Cylinder mesh motion is enabled, set the starting and ending crank angles for the injection in the Start Crank Angle and Stop Crank Angle fields.

• spray half angle

  Set the initial half angle of the drops as they leave the end of the orifice in the Spray Half Angle field.

• orifice width

  Set the width of the orifice (in the normal direction) in the Orifice Width field.

• sheet breakup

  Set the value of the empirical constant that determines the length of the ligaments that are formed after sheet breakup in the Flat Fan Sheet Constant field (see this equation in the separate Theory Guide).

• dispersion angle

  For a smooth distribution of the droplets, the initial velocities is varied within this dispersion angle. A scetch of the Atomizer Dispersion Angle is depicted in Figure  23.3.5.

See this section in the separate Theory Guide for details about how these inputs are used.

Figure 23.3.5: Flat Fan Viewed from Above and from the Side