What is it?
A useful way to visualize groundwater flow is to perform traditional particle tracking, in which particles undergoing only advection are introduced at various locations in the flow model, and path lines and travel times are simulated and visualized. Particle tracking allows delineation of path lines in a flow model, which be used, e.g., to determine well capture zones, source water areas, and groundwater delivery mechanisms.A. Particle Lines
B. Particle Zones
C. Particle Wells
D. 3D Release Surfaces
E. Save PTK Results
The ‘ParticleTK’ button along the left-side of the IGW-NET Modeling Environment (Simulation Tools > ParticleTK) provides access to the tools need to place particles. Click on it to bring up the Particle pop-up menu.
A. Particle Lines
Select ‘ParticleLine’ from the Particle pop-up menu to place particles along a polyline. The cursor will become a cross-hair, allowing for placement of polyline vertices with single-clicks. Once the last vertex has been placed, LM click the ‘SaveShape’ button to finalize the particle polyline.LIMITATION: For the free version of IGW-NET, the maximum number of particles allowed along a Pline is 50.
Vertical Settings for Particle Polylines
All particles are, be default, placed at the vertical mid-point of the aquifer layer (2D matrix at Z=0.5)
To move all particles to a different vertical position within the aquifer layer, input a value between 0.0 and 1.0 in the text field next to '2D maxtrix at Z=' (0.0 represents the aquifer bottom; 1.0 represnts the aquifer top).
Particles can also be distributed vertically by selecting '3D matrix' option and specifying an upper bound (Ztop) and lower (Zbot) bound for the vertical placement of the particles (again using 0.0 for aquifer bottom and 1.0 for aquifer top).
The 'Density factor' is the layer fraction between Ztop and Zbot (i.e., the relative distribution of particles in layer(s) closer to Ztop to the distribution of particles in layer(s) closer to Zbot).
Particle Zones
Select ‘ParticleRect’ (rectangle) or ‘ParticleZone’ (polygon) from the Particle pop-up menu to place particles inside of a zone polyline. The cursor will become a cross-hair, allowing for placement of rectangle/ polygon vertices with single-clicks. . Once the last vertex has been placed, LM click the ‘SaveShape’ button to finalize the particle zone.
LIMITATION: For the free version of IGW-NET, the maximum number of columns to allocated particles in a PZone is 20.
Vertical Settings for Particle Zones
All particles are, be default, placed at the vertical mid-point of the aquifer layer (2D matrix at Z=0.5)To move all particles to a different vertical position within the aquifer layer, input a value between 0.0 and 1.0 in the text field next to '2D matrix at Z=' (0.0 represents the aquifer bottom; 1.0 represents the aquifer top).
Particles can also be distributed vertically by selecting '3D matrix' option and specifying an upper bound (Ztop) and lower (Zbot) bound for the vertical placement of the particles (again using 0.0 for aquifer bottom and 1.0 for aquifer top).
The 'Density factor' is the layer fraction between Ztop and Zbot (i.e., the relative distribution of particles in layer(s) closer to Ztop to the distribution of particles in layer(s) closer to Zbot).
Particles Around a Well
To add particles around a well, check the radio box next to ‘Add Particle’. In the Particle Tracking option box, adjust the number of particles around a well by entering a value in the text box next to ‘Particle # Around a Well:’.Control the release distance around the well using the 'Particle Well Radius' input field.
LIMITATION: For the free version of IGW-NET, the maximum number of particles allowed around a is 30.