Stream-, streak- and pathline computation, with emphasis on per-droplet frames of reference.
The following input ports are available:
| Input | Description | Type | Remark |
|---|---|---|---|
| Input | Points (representing cells) of the octree, especially containing IDs to identify their position in the tree. | Rectilinear Grid | |
| Seed | Input seed for stream-, streak- and path lines. | Poly Data | |
| Droplets | Extracted droplet positions with corresponding properties. | Poly Data |
The input rectilinear grid contains the following data fields:
| Data field | Description | Data | Type | Remark |
|---|---|---|---|---|
| Droplet ID | ID to relate the cell to the corresponding droplet. | Scalar | Cell-based | Optional |
| Velocity field | Velocity at the cell's center. | Vector | Cell-based | |
| Volume of fluid field | Volume of fluid field, giving the volume fraction for each cell. | Scalar | Cell-based | Optional |
| Arrays | Interpolate at particle positions and store values along stream- or pathlines. | Point-based | Optional |
The input points representing the centers of the droplets contain the following data fields:
| Data field | Description | Data | Type | Remark |
|---|---|---|---|---|
| Droplet translation | Translation of the droplet at its center of mass. | Vector | Point-based | |
| Droplet rotation | Rotation of the droplet around its axis of rotation, given as angular velocity. | Vector | Point-based |
The following parameters can be set by the user:
| Parameter | Description | Type | Accepted values | Default value |
|---|---|---|---|---|
| Seed in cells | Seed in cells instead of using the input seed. | Boolean | True, False | True |
| Cell type | Choose in which cells seeds should be created. | Enum | All cells, Interface cells, Droplet cells | All cells |
| Seed size per cell | Number of seed points per cell. | Integer | >0 | 1 |
| Method | Type of the integral curves to compute. | Enum | Streamlines, Streaklines, Pathlines | Streamlines |
| Interpolatable | Is the data interpolatable? (Not the case for VOF data.) | Boolean | True, False | False |
| Integration | Integration method. Availability is based on interpolatability of the input. | Enum | Explicit Euler, Adams-Bashforth | Adams-Bashforth |
| Number of advections | Number of advection steps for streamline computation. | Integer | >0 | 20 |
| Time range | Time range for pathline and streakline computation. | [Float, Float] | [0.0, 1.0] | |
| Time step | Time step size for streamline computation and if the data is interpolatable. | Float | 0.1 | |
| Time dependency | Time dependency of the frame of reference, i.e., static vs. dynamic frame of reference. | Enum | Dynamic, Static | Dynamic |
| Keep translation | Do not remove translational velocity part. | Boolean | True, False | False |
| Keep rotation | Do not remove rotational velocity part. | Boolean | True, False | False |
The result of the computation are either stream-, streak or pathlines with the following data fields:
| Data field | Description | Data | Type | Remark |
|---|---|---|---|---|
| ID (advection) | Time information, storing the advection step. | Scalar | Point-based | |
| ID (distribution) | Time information, storing the advection step normalized for each integral line. | Scalar | Point-based | |
| Time | Time information, storing the time step. | Scalar | Point-based | |
| Seed ID | ID of the seed point, to discern individual integral lines. | Scalar | Point-based |