Thursday, November 16, 2023

πŸ’§ICM InfoWorks Link or Conduit 1D Solution Options πŸ’§

 πŸ’§ICM InfoWorks Link or Conduit 1D Solution Options πŸ’§

AspectConduit Model (Full Solution Model)Pressurised Pipe ModelForce Main ModelPermeable Solution ModelFinite Volume Solution Model
Basic DescriptionRepresents a link in the network, typically between two nodes.Used for specific cases like rising mains or inverted siphons.Advanced feature for pressurised systems, especially useful for long rising/force mains subject to low hydraulic heads.Used for modelling permeable pavements or similar structures.Developed for complex trans-critical flow scenarios, particularly useful for resolving hydraulic jumps within a conduit.
Key CharacteristicsBoundary conditions are of outfall or headloss type. <br> - Gradient defined by invert levels at each end. <br> - Variety of pre-defined cross-sectional shapes.Does not assign base flow or a Preissmann slot to a pipe. <br> - More accurately predicts velocities and storage.- Assumes pipe is always full.- Water level maintained at least to pipe soffit level. <br> - Can result in erroneous flow generation if used inappropriately.Governing equation based on Darcy's Law.Replaces individual conduit's solution while integrating with the existing node-matrix solver and boundary conditions. <br> - Utilizes a Roe Riemann solver for flux term resolution.
Model EquationsSaint-Venant equations (conservation of mass and momentum).Similar to the full model but with modifications for pressurised conditions.Uses the same equations as the Pressurised Pipe Model but with specific assumptions for application.Involves calculation of discharge using Darcy's Law and consideration of porosity and lateral inflow.Based on de Saint-Venant equations in conservative vector form for a control volume.
Hydraulic RoughnessTwo different values can be assigned for different parts of the conduit.Not specified.Not specified.Not specified.Not specified.
Sediment ConsiderationA permanent depth of sediment may be defined; no erosion or deposition considered.Not specified.Not specified.Not specified.Not specified.
Special Features- Non-standard cross-sectional shapes can be modelled. <br> - Preissmann slot for smooth transition between free surface and surcharged conditions.- Excludes modelling of the inertia term for pressure pipes if selected. <br> - Stay pressurised simulation parameters option to prevent negative depths.- Intermediate points such as junctions should be represented using break nodes. <br> - Negative hydraulic grade lines may occur.- Modelling of lateral inflow and porosity.- Capable of resolving transitions between sub- and super-critical flows. <br> - Implicit terms linearised with a first-order Taylor series expansion. <br> - Friction slope defined as a part of the equations.
Appropriate Use CasesSuitable for a wide range of scenarios including both closed pipes and open channels.Recommended for specific scenarios like rising mains where pressurisation is a key factor.Best used in pressurised pipes, particularly for long rising mains. Not recommended for gravity pipes.Ideal for scenarios involving permeable media.Best for scenarios where there are transitions between sub- and super-critical flows, and for accurately modelling hydraulic jumps.

This table provides a high-level comparison of the different solution models, highlighting their unique features, governing equations, and appropriate use cases. If you need more detailed information or specific aspects of these models, feel free to ask!

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Emoji EPANET2.2 Reference Table

  Author(s) Year Title Emoji Bhave 1991 Analysis of Flow in Water Distribution Networks πŸ“˜ Clark, R.M. 1998 Chlorine demand and Trihalometha...