An established method for directly determining the
kinetics of chlorine decay attributable to pipe-wall reactions
does not currently exist. Wide variability in wall
reaction parameters, attributable to varying characteristics
of a pipe such as age, material, and diameter, also make
the task of estimating these parameters tedious at best.
An inverse model that accurately estimates water
quality reaction parameters is developed. The parameter
estimation problem is formulated as an unconstrained
optimization problem, for which an inverse modeling
approach using a water quality simulation model and a
stochastic search genetic algorithm (GA) as routines in
the computational procedure is adopted.
Calibrating a water distribution model using
GA, which attempts to find the best solution by
mimicking the natural selection process in genetics,
can automate and simplify the process for any
applicable reaction kinetics. In addition, a GA-based
water quality calibrator is applicable to
many unknown individual, global, or grouped reaction
parameters.
Applying the inverse model to two real-life networks
demonstrated the model's ability to compute the various
types of unknown reaction parameters. GA was
found to be the most appropriate method to use with a
large number of parameters. Includes 22 references, tables, figures.