Steven L. Rowan

Express Risk Assessment throughWeb Access to Simulation Data

A prototype of an express risk assessment system is proposed and implemented as a combination of a distributed simulator and a Web interface. A case of aerosol dispersion in an urban environment is investigated. Fast response of the system is achieved by replacing complex 3D simulations with information retrieval from aerosol dispersion database. The database is created by extensive simulations of different aerosol dispersion scenarios. Cluster or grid computing environments are most suitable for these type of simulations. The reduction of system response from a few days to several seconds can be achieved compared to realtime 3D simulations

A Reduced Order Model for the Design of Oxy-Coal Combustion Systems

Oxy-coal combustion is one of the more promising technologies currently under development for addressing the issues associated with greenhouse gas emissions from coal-fired power plants. Oxy-coal combustion involves combusting the coal fuel in mixtures of pure oxygen and recycled flue gas (RFG) consisting of mainly carbon dioxide (CO2). As a consequence, many researchers and power plant designers have turned to CFD simulations for the study and design of new oxy-coal combustion power plants, as well as refitting existing air-coal combustion facilities to oxy-coal combustion operations. While CFD is a powerful tool that can provide a vast amount of information, the simulations themselves can be quite expensive in terms of computational resources and time investment. As a remedy, a reduced order model (ROM) for oxy-coal combustion has been developed to supplement the CFD simulations. With this model, it is possible to quickly estimate the average outlet temperature of combustion flue gases given a known set of mass flow rates of fuel and oxidant entering the power plant boiler as well as determine the required reactor inlet mass flow rates for a desired outlet temperature. Several cases have been examined with this model. The results compare quite favorably to full CFD simulation results.