Dear Dr. Isaac, thank you for your excellent episodes that enrich the scientific background of the professional engineering community. Imagine solving the same problem using EPA-SWMM instead of Stormcad, of course. It is expected to get different estimations simply because Bentley's package uses Rational whereas EPA's package adopts an overland Manning flow equation. My question is, as a designer, which peak flow number from both packages might you say I will go for it?
For Middle east,since worked in the projects, Muncipal authority will request for Stormcad model for review In the Storm cad/Civil storm,we can auto calculate tc for bigger catchments/Plots by assigning catchment parameter in 5-6 methods(like Slope,CN,flow path length), for smaller ROW catchments where it cattered by gully/gutter system we have to consider minimum tc as per the code say 5minutes or 10minutes
Hi Dr. Wait, thank you for sharing practical skills for design of stromwater drainage pipeline. May I ask the methodology of determination of time of entry/ time of concentration for urban (paved) area? I know there is a formula (i.e. Brandsby William's Equation) to calculate the time of concentration for natural catchment. However, I was told I should apply 3 mins for urban area but no one explained in detail. I am curious how the time of concentration (i.e. 3mins) for urban area came from.
For an urban area the time of concentration can be estimated by determining the distance between the farthest point away from an inlet or point of interest, and estimating the flow velocity at different stages on the path between that farthest point and the inlet. On a street, for example, some of the flow may be relatively slow-moving sheet flow over the surface of the pavement, and then a period of shallow concentrated flow where the velocity is somewhat higher, transitioning to deeper concentrated flow (e.g., in a gutter) where the flow velocity is higher still. So it's the travel time. Visiting the site on a rainy day may help. This video shows some equations that may also be useful. th-cam.com/video/i7lZWDVJGvI/w-d-xo.html
Watching it fro Ghana. thanks a lot.
Thank you - best wishes from West Virginia!
Hey Dear, thank you so much for sharing this video. Watching it from Qatar. Thanks alot
Thanks for your nice comment. I love Doha, and hope that I will be able to visit there again someday.
@@IsaacWait Oh thats great you were here.😍
Dear Dr. Isaac, thank you for your excellent episodes that enrich the scientific background of the professional engineering community. Imagine solving the same problem using EPA-SWMM instead of Stormcad, of course. It is expected to get different estimations simply because Bentley's package uses Rational whereas EPA's package adopts an overland Manning flow equation. My question is, as a designer, which peak flow number from both packages might you say I will go for it?
For Middle east,since worked in the projects, Muncipal authority will request for Stormcad model for review
In the Storm cad/Civil storm,we can auto calculate tc for bigger catchments/Plots by assigning catchment parameter in 5-6 methods(like Slope,CN,flow path length), for smaller ROW catchments where it cattered by gully/gutter system we have to consider minimum tc as per the code say 5minutes or 10minutes
Hi Dr. Wait, thank you for sharing practical skills for design of stromwater drainage pipeline. May I ask the methodology of determination of time of entry/ time of concentration for urban (paved) area? I know there is a formula (i.e. Brandsby William's Equation) to calculate the time of concentration for natural catchment. However, I was told I should apply 3 mins for urban area but no one explained in detail. I am curious how the time of concentration (i.e. 3mins) for urban area came from.
For an urban area the time of concentration can be estimated by determining the distance between the farthest point away from an inlet or point of interest, and estimating the flow velocity at different stages on the path between that farthest point and the inlet. On a street, for example, some of the flow may be relatively slow-moving sheet flow over the surface of the pavement, and then a period of shallow concentrated flow where the velocity is somewhat higher, transitioning to deeper concentrated flow (e.g., in a gutter) where the flow velocity is higher still. So it's the travel time. Visiting the site on a rainy day may help. This video shows some equations that may also be useful. th-cam.com/video/i7lZWDVJGvI/w-d-xo.html
@@IsaacWait Thank you for your explanation. I also love your videos which refresh my mind. 🙌
Can you send me the file please??