Using Injection Tables

Injection tables are the input method for table injectors. These tables specify the location of injection points and the time of injection. They can also specify some properties of the injected parcels.

There are three kinds of injection table:

  • Injection Points table
  • Unsteady Injection Points table
  • Parcels table

Injection Points Table

Injection Points tables are available with both steady and unsteady Lagrangian Multiphase simulations. A table injector using an Injection Points table has the following features:

  • Each row of the table represents an injection point.
  • Any injection point that is not in the parts specified under the injector Inputs property is discarded.
  • The injector uses the Parcel Streams value for the number of parcel streams per injection point.
  • Parcels are injected according to the Update Frequency property of the solver.
  • The injector can use any of the Flow Rate Distribution options, but only the Per Injector Point or Per Parcel Stream options allow you to specify the flow rate in the injection table.
  • The table can include any properties of the parcels listed under the physics values node of the injector. Examples of such properties include particle diameter, velocity, temperature, passive scalar values, parcel mass fraction, and parcel mole fraction.

Example table:

X(cm) Y(cm) Z(cm) Diameter U V W Mass Flow Rate Temperature
0 0 6.0 1.e-05 0 0 0.001 0.001 350
0 0 2.0 2.e-05 0.002 0.001 350

Injection Points Table Properties

The table is represented by a node named Injection Points Table, located under the injector Values node. The table node has the following properties:

Table The table name, selected by drop-down menu from the tables defined under Tools > Tables. The default is None.
X coordinate The names specified in the table for the columns for the X, Y, and Z coordinates. For the example table in this section, the entries would be X(cm), Y(cm), and Z(cm).
Y coordinate
Z coordinate
Coordinate System The coordinate system in which the injection points are specified. This can be the laboratory system or a local coordinate system you have created. This coordinate system applies only to the injection points, not to any other related properties, such as velocity. The default is Laboratory.

Unsteady Injection Points Table

Unsteady Injection Points tables are available only with unsteady Lagrangian Multiphase simulations. A table injector using an Unsteady Injection Points table has the following features:

  • Each row of the table represents an injection point at a specific time value.
  • The total number of injection points is equal to the maximum index found in the table.
  • Each injection point is identified in the table by a unique positive index.
  • Numbering for the injection point indices starts from 1.
  • For every injection point index, there is at least one row in the table.
  • For every injection point index, the time values must be specified in ascending order.
  • At any given time, for each injection point index, the locations are interpolated in time as follows:

    • If the current value of time is less than the minimum time value found for that injection point, parcels are injected from the location corresponding to the minimum time value.

    • If the current value of time is greater than the maximum time value found for that injection point, parcels are injected from the location corresponding to the maximum time value

  • Any injection point that is not in the parts specified under the injector Inputs property is discarded.
  • The injector uses the Parcel Streams value for the number of parcel streams per injection point.
  • Parcels are injected according to the Update Frequency property of the solver.
  • The injector can use any of the Flow Rate Distribution options, but only the Per Injector Point or Per Parcel Stream options allow you to specify the flow rate in the injection table.
  • The table can include any properties of the parcels listed under the physics values node of the injector. Examples of such properties include particle diameter, velocity, temperature, passive scalar values, parcel mass fraction, and parcel mole fraction.

Example table, for a simulation with time-step of 0.001:

Index X(cm) Y(cm) Z(cm) Diameter Time
1 0 0 1.0 1.e-05 0.0012
2 0 0 2.0 2.e-05 0.0022
1 0 0 3.0 3e-05 0.0032
3 0 0 3.0 3e-05 0.0035
2 0 0 4.0 4e-05 0.0042

There are three injection points, indexed 1, 2, and 3. At every time-step, all three injection points inject parcels. At every time-step, the position of the injection point is interpolated, based on the values given in the table.

  • For the time 0.001, corresponding to the first time-step, points inject from their earliest given position. For example, the earliest time specified for point 1 is 0.0012 s, which is greater than the current physical time, so point 1 injects from position 1 cm.
    Injection Point Position
    1 1 cm
    2 2 cm
    3 3 cm
  • At time 0.002, corresponding to the second time-step, there are no positions specified for points 1 or 3.

    • Point 1 injects from a position between 1 cm and 3 cm; the exact position depends on the interpolation option specified.

    • Point 3 injects from a position of 3 cm, because that is still its earliest specified position.

  • At time 0.003, corresponding to the third time-step, there are no positions specified for points 2 or 3.

    • Point 2 injects from a position between 2 cm and 4 cm; the exact position depends on the interpolation option specified.

    • Point 3 injects from a position of 3 cm, because that is still its earliest specified position.

  • After the value for time passes 0.004, all three injection points inject parcels from the position for the last, highest time value:
    Injection Point Position
    1 3 cm
    2 4 cm
    3 3 cm

Unsteady Injection Points Table Properties

The table is represented by a node named Unsteady Injection Points Table, located under the injector Values node. The table node has the following properties:

Table The table name, selected by drop-down menu from the tables defined under Tools > Tables. The default is None.
X coordinate The names specified in the table for the columns for the X, Y, and Z coordinates. For the example table in this section, the entries would be X(cm), Y(cm), and Z(cm).
Y coordinate
Z coordinate
Coordinate System The coordinate system in which the injection points are specified. This can be the laboratory system or a local coordinate system you have created. This coordinate system applies only to the injection points, not to any other related properties, such as velocity. The default is Laboratory.
Time The name of the column listing time values (read-only). The column in the table must be named time, Time, or TIME.
Injection Point Index The name of the column listing a unique positive index for each injection point (read-only). The column in the table must be named index, Index, or INDEX.

Expert Properties

Interpolation Selects interpolation method, Spline, Step, or Linear.

Parcels Table

Parcels tables are available only with unsteady Lagrangian Multiphase simulations. A table injector using a parcels table has the following features:

  • Each row of the table represents a parcel at a specific time value.
  • Parcels are injected only at the times specified in the table. There is no interpolation.
  • A set of rows with time values that lie between the current physical time and the current physical time plus the time-step are treated as a single block of parcels and are injected at the start of the most recent time-step.
  • Any parcel that is not in the parts specified under the injector Inputs property is discarded.
  • The injector uses the Particle Count value for the number of particles per parcel.

    This value can be constant or read from the injection table.

    This value is taken as 1 if the DEM model is active, or if the value is not set.

  • The table can include any properties of the parcels listed under the physics values node of the injector. Examples of such properties include particle diameter, velocity, temperature, passive scalar values, parcel mass fraction, and parcel mole fraction.

Example table, for a simulation with time-step of 0.001:

X(cm) Y(cm) Z(cm) Diameter Time
0 0 1.0 1.e-05 0.0
0 0 2.0 2.e-05 0.0
0 0 3.0 3e-05 0.003
0 0 4.0 3e-05 0.0031
0 0 5.0 4e-05 0.0032

The table has two time blocks, corresponding to injection times 0.0 and 0.003 seconds.

  • There are two parcels in the first time block, and three parcels in the second time block.
  • In the first time step (corresponding to physical time = 0.001) two parcels are injected from 1.0 cm and 2.0 cm.
  • In the second time step (corresponding to physical time = 0.002), no parcels are injected.
  • In the third time-step (corresponding to physical time = 0.003), no parcels are injected.
  • In the fourth time step (corresponding to physical time = 0.004) three parcels are injected from 3.0 cm, 4.0 cm and 5.0 cm.

Parcel Table Properties

The table is represented by a node named Parcels Table, located under the injector Values node. The table node has following properties:

Table The table name, selected by drop-down menu from the tables defined under Tools > Tables. The default is None.
X coordinate The names specified in the table for the columns for the X, Y, and Z coordinates. For the example table in this section, the entries would be X(cm), Y(cm), and Z(cm).
Y coordinate
Z coordinate
Coordinate System The coordinate system in which the injection points are specified. This can be the laboratory system or a local coordinate system you have created. This coordinate system applies only to the injection points, not to any other related properties, such as velocity. The default is Laboratory.
Time The name of the column listing time values. The column in the table must be named time, Time, or TIME.