A close-up view of 3-inch Parshall flume nested in a 6-inch Parshall flume. Openchannelflow is unique in that special molds have been created that integrate the transitions from the larger flume into the smaller flume (and back).

Nested, or dual range flumes, allow operatores to measure to distinct flow regimes over time. In this case the smaller flume has been secured to the inside of the larger flume. Once the smaller flume is removed, the operator need only apply a small dab of silicone on each attachment point to seal it.