Optimal plume control

Key words groundwater remediation design, optimal plume control, groundwater quality management... 

Pumping rates at the two wells shown are systematically altered and the constraint function pk for 108 plume control points is determined. The sum of squared constraint values for each set of pumping rates is shown graphically in Figures 4a and 4b for confined and unconfmed assumptions, respectively. The minimum saturated thickness at the grid cells containing the two extraction wells is also shown on Figure 4b. The optimal solution... 

Methods of near-field, midfield and ensemble (global) imaging and real-time visualization have been developed for monitoring gas atomization of liquid metals.[327] The primary process sensors and monitors used include high-speed video and infrared imaging systems. The process monitors allowed continuous and detailed observations of the atomization process and enabled measurements of the key parameters necessary for adequate control and optimization of the process. The sensors provided the operators with real-time information on the temperature of nozzle tip, visual characteristics of atomization plume, and gas and metal flow rates. The images can be displayed in real time, offering the potential for more responsive process control. 

Three general classes of optimization models for groundwater plume containment design are described in the literature, including hydraulic control models, advective control models, and concentration control models. All three classes of optimization models require that the groundwater flow... 

In this paper, the advective control model for groundwater plume capture design is described, algorithmic requirements to accommodate unconfined aquifer simulation are presented, and two- and three- dimensional example problems are used to demonstrate the optimization model capabilities and design implications. The model is applicable for designing long-term plume containment systems and as such assumes steady-state flow and time-invariant pumping. 

The two contaminant plumes are represented in the first stage of the optimization formulation with a set of 110 control points along the plume boundaries. These same control point locations are used as starting points for particles when forward tracking is used in the second stage of the solution process. For the unconfined simulation, additional constraints are included to require a minimum saturated thickness of 1.5 m at each well cell. Both confined and unconfined assumptions are simulated under two sets of penalty parameters. Recall that the solution algorithm uses the penalty method for the plume capture constraints, in which each constraint violation is multiplied by a penalty parameter and added to the objective function. 

Mulligan, A. E. (1999). Advective Control of Groundwater Contaminant Plumes Using Simulation and Optimization. PhD dissertation, University of Connecticut, Storrs. 

For such plumes to be created and maintained for long time periods, much work on controlled release systems in aquatic environments will be needed. In the insect world, dispensers have had to be optimized on a trial-and-error basis, based on behavioral reactions (trap catch) to various dispenser types and pheromone loading rates. Optimization has had to be assessed on a species-by-species trial system because each species has different pheromone components comprised of differing molecular weights and functionalities such as aldehydes, alcohols, and acetates. The field longevity of these same dispensers had to be similarly assessed based on trap capture levels over time. 

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