Author(s): Jorge Matos; Kathleen H. Frizell
Linked Author(s): Jorge Matos
Keywords: No Keywords
Abstract: The U. S. Bureau of Reclamation (Reclamation) developed instrumentation to measure air concentration and water velocity in a large, outdoor flume (Frizell at al, 1994). Recently, Reclamation redesigned these instruments for use in smaller indoor models, namely the stepped spillway model assembled at the National Laboratory of Civil Engineering (LNEC), Lisbon. The basic components of the air concentration probe and its operation and calibration are discussed in this paper. Typical air concentration profiles are also shown, highlighting the highly aerated feature of skimming flows over stepped spillways. The experimental results are in agreement with the findings of Ruff and Frizell (1994) and with the analysis of Matos and Quintela (1995), which indicate that the equilibrium mean air concentration is similar to that obtained on smooth spillways of identical slope.
Year: 1997