Emojis - ICM InfoWorks - 🌊💡 2D Inlet Node Parameters Explained 💡🌊

· October 21, 2023

 🌊💡 2D Inlet Node Parameters Explained 💡🌊

🛣️ On the Roadway: As we've previously discussed, when you're diving into continuous inlets, you're going to want some specific details from that roadway! For your Inlet input type titled 'Params', here's what you'll need:

🔗 Continuous Grate Inlet: Get both the inflow and the velocity🌪️. 🔗 Continuous Curb-Opening Inlet: Just the inflow will do!🌊. 🔗 Continuous UPC Grate Inlet: You'll need the inflow and the half road width (denoted as x)📏.

🚧 When using a 1D model for your inlet, the road's flow, or Q, comes from the overland conduits that connect to the inlet's upstream end. But with 2D inlets, you must specify a Cross slope to calculate that inflow.

📚 Doing the Math: Let's break down the equations!

Qinflow = A . v (Equation 22📝) is where:

  • v is the velocity in the mesh element containing the inlet node 🌪️.

A = 0.5 . T .d (Equation 23📝) is determined by:

  • d being the depth in the mesh element containing the inlet node 🌊.

T = d/Sx (Equation 24📝) is where:

  • Sx is your cross slope, provided by you, the user! ⛷️.

🔶 UPC Grate Needs: For this, a Half road width value is essential for a 2D inlet.

🕳️ Sag Inlets: These inlets are first modeled as weirs, but after reaching a specific depth, they transition to being modeled as orifices. You'll need a user-defined depth value for all sag inlet types. The equations used here are inspired by the FHWA HEC 22 Urban Drainage Manual.

🔳 Grate Inlet Needs: Your Node Property Sheet will ask for:

  • Width of grate📏.
  • Length of grate📐.
  • Clear opening area of grate⬛.

A clogging factor might also be in the picture, representing a reduction in the grate's width.

🔵 Curb-opening Inlet: Your Node Property Sheet should include:

  • Length of curb opening📏.
  • Lateral width of gutter depression🔍.
  • Height of the curb opening📊.

🌈 Combination Inlet: For this, you'll need:

  • Width of grate📏.
  • Length of grate📐.
  • Clear opening area of grate⬛.
  • Height of the curb opening📊.
  • Length of the curb opening📈.

A clogging factor may come into play again, indicating a potential reduction in the grate's width.

By understanding and utilizing these parameters, you can ensure optimal performance and accurate modeling of your inlets! 🎉📚🌊.