SWMM56

Overview In this blog we show how the St Venant terms are used in SWMM5 as equations, table, graphs and units. We use a QA/QC version of SWMM 5 that lists many more link, node, system and Subcatchment variables than the default SWMM 5 GUI and engine. This also applies to #InfoSWMM and any software the uses the #SWMM5 engine. SWMM5 is using is the most advanced equations as it takes into consideration the full dynamic (St. Venant) equations and not the more simplified kinematic wave / manning equations. The manning equation only considers the uniform flow conditions which represents a situation where the gravitational force on a column of water (due to the channel slope) balances out the frictional force. The full dynamic equations contains additional factors that affect the movement of water in a conduit or channel. These include the pressure force due to variation of depth along the length of the channel and the inertial (or convective acceleration) effect due to variation of flow ar...

How to Tell how Long Normal Flow is used in a Link in #InfoSWMM, H2OMap SWMM  w/ #SWMM5 Find the Fraction of Normal Flow Limited in the Flow Classification  Table and copy it to the Link Information Table - the value of FLM can then be Displayed in a Map using  the Map Display command.  In this small example, three links primarily used normal flow and one uses it for a short time. Normal flow only uses the Manning's equation and the link upstream depth, hydraulic radius and cross sectional area to compute the flow. How to Tell how Long Normal Flow is used in a Link in #InfoSWMM, H2OMap SWMM  w/ #SWMM5 St. Venant equation  solution – this is the link attribute data used when the St. Venant Equation is used in #SWMM 5. Simulated Parameters from the upstream, midpoint and downstream sections of the link are used. Normal Flow Equation  – this is the link attribute data used when the Normal Flow Equation is used in #SWMM 5. Onl...

This blog contrasts the St Venant Solutions for InfoSewerH20Map Sewer (1), InfoSWMM/H2OMap SWMM and ICM/ICM SE. 1.  Assumptions for the St. Venant Equations The assumptions behind Lumped and Distributed Models along with the assumptions of the  St Venant equations .  InfoSewerH20Map Sewer, InfoSWMM, H2OMap SWMM, SWMM5, ICM and ICM SE are all Distributed models for Unsteady flow.  InfoSWMM and InfoSewerH20Map Sewer have options for direct steady flow.  ICM and InfoSWMM can also use a quasi steady flow solution.   All of these Innovyze models use the Continuity Equation and Momentum equation for routing flows in links.  The numerical solution differs between the three Innovyze main  platforms: InfoSewer and H2OMap Sewer InfoSWMM,  H2OMap SWMM and SWMM 5 ICM and ICM SE Continuity Equation Various Forms of the Momentum Equation 2.  Muskingum-Cunge for InfoSewerH20Map Sewer The continuity (mass conservation) equation is: where x ...

Storm Water Management Model   From Wikipedia, the free encyclopedia The  United States Environmental Protection Agency  (EPA)  Storm Water Management Model  (SWMM) [ 1 ] [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 6 ] [ 7 ]  is a dynamic rainfall– runoff – subsurface runoff   simulation model  used for single-event to long-term (continuous)  simulation of the surface/subsurface hydrology quantity and  quality  from primarily urban/suburban areas. The hydrology component of SWMM operates on a collection of  subcatchment areas  divided into  impervious  and  pervious  areas with and without  depression  storage to predict  runoff  and  pollutant  loads from precipitation, evaporation and  infiltration losses from each of the subcatchment. In addition low impact development (LID) and best management practice areas on the subcatchment can be modeled to reduce the impervious and pervious ru...