A simple aerosol transport model was developed for a multi-compartmented cleanroom. Each compartment was treated as a well-mixed volume with ventilating supply and return air. Gravitational settling, intercompartment transport, and leakage of exterior air into the system were included in the model. A set of first order, coupled, ordinary differential equations was derived from the conservation equations of aerosol mass and air mass. The system of ODEs was then solved in MATLAB using pre-existing numerical methods. The model was verified against cases of (1) constant inlet-duct concentration, and (2) exponentially decaying inlet-duct concentration. Numerical methods resulted in normalized error of less than 10 -9 when model solutions were compared to analytical solutions. The model was validated against experimental measurements from a single field test and showed good agreement in the shape and magnitude of the aerosol concentration profile with time.
The primary goals of the Enhanced Micellar Catalysis project were to gain an understanding of the micellar environment of DF-200, or similar liquid CBW surfactant-based decontaminants, as well as characterize the aerosolized DF-200 droplet distribution and droplet chemistry under baseline ITW rotary atomization conditions. Micellar characterization of limited surfactant solutions was performed externally through the collection and measurement of Small Angle X-Ray Scattering (SAXS) images and Cryo-Transmission Electron Microscopy (cryo-TEM) images. Micellar characterization was performed externally at the University of Minnesotas Characterization Facility Center, and at the Argonne National Laboratory Advanced Photon Source facility. A micellar diffusion study was conducted internally at Sandia to measure diffusion constants of surfactants over a concentration range, to estimate the effective micelle diameter, to determine the impact of individual components to the micellar environment in solution, and the impact of combined components to surfactant phase behavior. Aerosolized DF-200 sprays were characterized for particle size and distribution and limited chemical composition. Evaporation rates of aerosolized DF-200 sprays were estimated under a set of baseline ITW nozzle test system parameters.