A framework for developing synthetic chemical and biological agent release data sets

Our nation invests heavily in technologies to defend against the hostile use of chemical and biological (CB) weapons and ensure that Department of Defense (DoD) operations remain unconstrained by a CB attack. The new contamination avoidance systems now being developed and tested are key to meeting this requirement. The robust system development and testing of these technologies requires the extensive use of observational data sets. Unfortunately, it is not cost-effective to create the large quantity of data sets necessary for this task through simulated-agent or live-agent testing. Virtual-environment test data sets provide a powerful tool that can be used to overcome this challenge. This presentation will describe a modeling and simulation framework currently under development that is designed to meet this critical need. This framework, called the Virtual THreat Response Emulation and Analysis Testbed (VTHREAT), accomplishes this task by utilizing a variety of research grade atmospheric and transport and dispersion (T&D) models to generate physically realistic four-dimensional representations of the CB agent behavior in various turbulent atmospheric environments. These virtual environments may then be probed by virtual CB sensor platforms, to evaluate their performance under varying atmospheric regimes, background interferent levels, and CB release scenarios. One of the core modeling components, called the EULerian semi-LAGrangian research model for geophysical flows (EULAG), can utilize Direct Numerical Simulation (DNS) or Large Eddy Simulation (LES) numerical techniques for simulating atmospheric turbulent flows and is used extensively by the atmospheric turbulence community. Within VTHREAT, EULAG has been coupled to a Lagrangian Particle Dispersion Model (LPDM) to simulate the turbulent transport and dispersion of a CB material release. The combined EULAG/LPDM system has undergone preliminary evaluations characterizing its ability to produce realistic virtual CB dispersion patterns, has been used to support field test planning/design, and is being enhanced to test future CB defense applications. Examples of these evaluations and applications will be presented along with a discussion of future plans. The presentation will also include a demonstration of the latest VTHREAT User Interface (UI).