SMS:PTM

PTM
PTM Screenshot
Model Info
Model type	Lagrangian particle tracker designed to allow simulating particle transport processes.
Developer	Neil J. MacDonald, Ph.D. Michael H. Davies, M.Sc., Ph.D., P.Eng. Coldwater Consulting Ltd
Web site	PTM web site

The Particle Tracking Model (PTM) is a Lagrangian particle tracker designed to allow simulating particle transport processes. PTM is funded through two US Army Corps of Engineers Engineering Research and Development Center (ERDC) research programs, the Coastal Inlets Research Program (CIRP) and the Dredging Operations and Environmental Research (DOER) Program.

The PTM model can be added to a paid edition of SMS.

Functionality

PTM has been developed for application to dredging and coastal projects including dredged material dispersion and fate, sediment pathway and fate, and constituent transport. The model contains algorithms that appropriately represent transport, settling, deposition, mixing, and resuspension processes in nearshore wave/current conditions. It uses waves and currents developed through other models and input directly to PTM as forcing functions.

Using the Model / Practical Notes

• The horizontal and vertical coordinates used for all PTM input files must be in meters. Geographic coordinates cannot be used since it is a latitude/longitude system defined in decimal degrees.
• If last step trap is checked, the traps will not become active until the last time step.
• The Q3D advection option has been deprecated starting with SMS 11.1. The 2D advection option should be used instead.

How do I use PTM?

The SMS tutorials are a good place to start learning to use SMS and associated models. A tutorial is available for PTM.

Graphical Interface

SMS provides a graphical interface that is designed to visualize the projects being created, easily modify project parameters, and view the solutions produced by the PTM model. See PTM Graphical Interface for more information.

The PTM graphical interface contains tools to create and edit a PTM simulation. The simulation consists of a geometric definition of the sources, traps, and a set of numerical parameters. The parameters define the hydrodynamic input and options pertinent to the model.

The interface is accessed by selecting the Particle module and setting the current model to PTM. If a simulation has already been created or an existing simulation read, the particle object will exist in the Project Explorer and selecting that object will make the Particle module active and set the model to PTM. See the Particle module documentation for guidance on visualizing results.

The interface consists of the Particle module menus and tools augmented by the PTM menu. See PTM Graphical Interface for more information.

PTM Menu

The PTM menu becomes active when a PTM model coverage has been created. For more information see PTM Graphical Interface.

Tools

PTM sources and traps are created in the Map module as feature objects using the Map module tools.

PTM Coverages

In the SMS interface, two types of coverages can be applied to a PTM simulation. These include:

• PTM Source/Trap Coverage – Used to define input for a PTM simulation.
• PTM Gage Coverage – Used to view time series of output data computed by the PTM engine.

PTM Files

See the PTM Files page for a list of input and output files with a brief description.

Theoretical Basis / Mathematical Details

Please refer to the model developer provided documentation listed in the external links section.

Numeric Engine Background

Please refer to the model developer provided documentation listed in the external links section.

General Steps to Build a PTM Model

1. Open SMS
2. Although not required, it is generally easier to visualize the model if reading in the hydrodynamic solution
3. Convert the horizontal and vertical coordinates to meters. PTM cannot be run in Geographic Coordinates since it is a latitude/longitude system defined in decimal degrees.
4. Switch to the Map module
5. Create a PTM type coverage
6. Create sources and traps using feature points, arcs, and polygons
7. Switch to the Particle module
8. Use the PTM menu to create a new PTM simulation
9. Use the PTM menu to open the PTM Model Control dialog
   1. Specify input and output parameters in the model control
   2. Click on the Create input file(s) from data button to create a native sediment file, and hydrodynamic input files if needed. You may use mesh, water surface elevation, and velocity data from another model (ADCIRC, ADH, RMA2) to create the necessary fort.15 and/or *.h5 file.
10. Save the simulation
11. Use the PTM menu to perform a model check
12. Use the PTM menu to run PTM

General Post-Processing Steps

1. Use the display options to visualize the results
2. Use the Data Calculator or Create Datasets dialog to create particle datasets
3. Create a Cartesian Grid and use the Create Grid Datasets dialog to create Cartesian grid datasets
4. Review the Trap Output files in an ASCII file viewer

External Links

• U.S. Army Corps of Engineers DOER PTM website [1]
• 2005 ERDC TN-DOER-D4 Particle Tracking Model (PTM) in the SMS: I. Graphical Interface [2]
• 2005 ERDC TN-DOER-D5 Particle Tracking Model (PTM): II. Overview of Features and Capabilities [3]
• 2005 ERDC TN-DOER-D6 Particle Tracking Model (PTM) in the SMS: III. Tutorial with Examples [4]
• 2006 ERDC/CHL TR-06-20 PTM: Particle Tracking Model Report 1: Model Theory, Implementation, and Example Applications [5]
• 2008 ERDC/CHL CHETN-IV-71 Particle Tracking Model (PTM) in the SMS 10: IV. Link to Coastal Modeling System [6]
• 2007 The Particle Tracking Model: Description and Processes [7]
• 2009 Assessment of Dredging-Induced Sedimentation on Winter Flounder Spawning habitat [8]
• 2012 Use of the PTM with CMS Quadtree Grids[9]

Related Topics

• Particle Module
• Mesh Module