<< Click to Display Table of Contents >> Navigation:  Wadiso 6 User Guide > Time/Water quality simulation > Time/WQ techniques and general concepts > Time/WQ Modelling capabilities

Full-featured and accurate hydraulic modelling is a prerequisite for doing effective time simulation and water quality modelling. Wadiso, through the built-in EPANet, contains a state-of-the-art hydraulic analysis engine, that includes the following capabilities:

•computes frictional head loss, using the Hazen-Williams or Darcy-Weisbach formulas

•includes minor head losses for bends, fittings, etc.

•models constant or variable speed pumps

•computes pumping energy and cost

•models various types of valves, including shut-off, check, pressure regulating, and flow control valves

•allows storage tanks to have any shape (i.e., diameter can vary with height)

•considers multiple demand categories at nodes, each with its own pattern of time variation

•models pressure-dependent flow issuing from emitters (sprinkler heads), and can base system operation on both simple tank level or timer controls, and on complex rule-based controls.

 

In addition to hydraulic modelling, the following water quality modelling capabilities are provided:

•models the movement of a non-reactive tracer material through the network over time

•models the movement and fate of a reactive material as it grows (e.g. a disinfection by-product) or decays (e.g. chlorine residual) with time

•models the age of water throughout a network

•tracks the percent of flow from a given node reaching all other nodes over time

•models reactions, both in the bulk flow and at the pipe wall

•uses n-th order kinetics to model reactions in the bulk flow

•uses zero or first order kinetics to model reactions at the pipe wall

•accounts for mass transfer limitations when modelling pipe wall reactions

•allows growth or decay reactions to proceed up to a limiting concentration

•employs reaction rate coefficients that are modified on a pipe-by-pipe basis

•allows wall reaction rate coefficients to be correlated to pipe roughness

•allows for time-varying concentration or mass inputs at any location in the network

•models storage tanks as being either complete mix, plug flow, or two-compartment reactors.

 

By employing these features, water quality phenomena such as the following can, for instance, be studied:

•blending water from different sources

•age of water throughout a system

•loss of chlorine residuals

•growth of disinfection by-products

•tracking contaminant propagation events.