Cutthroat Flume Design
The Cutthroat flume has a flat floor throughout the flume and has an hourglass shape when viewed from above with the shorter section upstream.
With flat walls, the converging section of the flume is 1/3rd the length of the flume, with walls that contract at a uniform 3:1 ratio.
Unlike many other flumes, the Cutthroat flume lacks an extended throat – hence the name “Cutthroat”. The walls of the converging section narrow until they reach the throat, at which time they then immediately begin to expand in the diverging section.
Like the converging section, the walls of the diverging section are flat and diverge at a constant ratio (6:1). The diverging section is 2/3rd the length of the flume.
Two types of Cutthroat Flumes have been designed: Rectangular and Trapezoidal. Both types follow the general configuration laid out above. The difference being that the walls of the Rectangular Cutthroat Flume are vertical and those for the Trapezoidal Cutthroat Flume angle out (like a Trapezoidal flume).
Cutthroat Flume Dimensions
Like the Trapezoidal flume, the dimensions for the Cutthroat flume are not subject to a national standard, but are instead presented in various academic journals.
- Skogerboe, G., Bennett, R., Walker, W., Generalized Discharge Relations for Cutthroat Flumes, Journal of the Irrigation and Drainage Division, Vol. 98, No. IR4, December 1972
- Bennett, R., Cutthroat Flume Discharge Relations, Water Management Technical Paper No. 16, Colorado State University, AER71-72RSB6, March 1972