Submerged Flow
Lacking the throat and discharge sections of the standard Parshall Flume design, the Montana Flume is not intended for use in applications where submergence could be present.
While some studies have been conducted on submerged flow in Montana Flumes, designing for submergence is not recommended. Openchannelflow recommends that Montana Flume installations provide for free-spilling discharge under all flow conditions. If submergence is possible, a full-length Parshall Flume should be used.