Drainage and Utilities supports modeling area-based orifice openings which are aligned horizontally and vertically, expressed as oriented parallel or perpendicular to flow direction, respectively. Orifices which are oriented parallel to flow do not require a datum input (since it is assumed to be equal to the opening invert).

In Drainage and Utilities, circular orifices are all oriented perpendicular to flow. To model an opening oriented parallel with flow, use the Orifice-Area option, or a Stand Pipe.

Related Topics

• "Orifices"
• "Submerged Orifice Hydraulics"
• "Circular Unsubmerged Hydraulics"
• "Orifice Area Unsubmerged Hydraulics"