Stormwater Management Model (SWMM) Information for watershed water quality, hydrology and hydraulics modelers (Note this Blog is not associated with the EPA). You will find Blog Posts and Twitter Embeds on the Subjects of SWMM5, InfoSWMM, InfoSewer, SWMMLive, InfoSWMM SUSTAIN, SWMM4 and SWMM in general.
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How is the Soil Saturated Conductivity Used in SWMM 5 Green-Ampt?
Subject: How is the SoilSaturatedConductivityUsed in SWMM5Green-Ampt?
How sensitive is the infiltration loss and rate to the SoilSaturatedConductivity parameter in the SWMM5Green-Ampt infiltration method. Figure 2 shows how the total infiltration loss and total loss rate vary as you change the soilsaturatedconductivity from 1 to 0.1 to 0.01 inches/hour. Internally, Ks is used to check saturation and in the computation of the soil infiltration rate. Two of the checks are:
· In low rainfall everything infiltrates as irate less than Infil>Ks and · In the check to see if the soil is already saturated.
Figure 1. The three parameters for Green-Ampt Infiltration in SWMM5
Figure 2. The sensitivity of the total infiltration loss to the soilsaturatedconductivity in a continuous simulation
Comment: A really nice water analogy for the field properties Divergence, Curl and Gradient from the Blog Starts With a Bang
....it's pretty mathematically intensive, but what's missing from most textbooks and E&M courses are physical explanations of what the mathematics means. For instance, I've started teaching about fields, and pretty much every textbook out there goes on and on about the properties of fields. They say you can do three things to fields, take the gradient, divergence, orcurl of them. (Are you asleep yet? I'm sorry!) What do these things mean? An easy way to picture it is in terms of water. If you placed a drop of water anywhere on, say,Earth, the magnitude and direction of how it rolls down is the gradient of the Earth's elevation. If you let that drop of water flow, as it goes downhill, it can either spread out or converge to a narrower stream. When we quantify that, that's what the divergence of the field is. And finally, when that water is …
Soffit Level (pipe technology)The top point of the inside open section of a pipe or box conduit. The soffit is the highest point of the internal surface of a pipe or culvert at any cross-section. The soffit is also referred to as the pipe obvert. So it is not quite the Crown of the Pipe. Here is an image I found that hopefully explains it better.
Engine Error NumberDescription ERROR 101: memory allocation error. ERROR 103: cannot solve KW equations for Link ERROR 105: cannot open ODE solver. ERROR 107: cannot compute a valid time step. ERROR 108: ambiguous outlet ID name for Subcatchment