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Two-Phase Flow Measurements

Dual-tipped optical probes were developed and constructed to measure gas volume fraction, bubble velocities, and bubble sizes.

Dual-tipped optical probes.

Dual-tipped optical probes.

Data was collected on the 1:24 scale laboratory model of the future unit fish bypass at Wanapum Dam to evaluate the behavior of bubbles under different spillway flow regimes.

The 1:24 scale laboratory model of the future unit fish bypass at Wanapum Dam.

The 1:24 scale laboratory model of the future unit fish bypass at Wanapum Dam.

The instrument was tested in a full-scale ship with velocities similar to those found in hydropower tailraces.

Testing in a full-scale ship.

Testing in a full-scale ship.

Reduced-Scale Models and River Survey

Our group has extensive experience in field studies and physical modeling of hydrodynamic features of large hydropower projects, with a strong historical emphasis on dams and natural channels. Physical modeling of many of these structures required comprehensive 3-D replication of bathymetry and civil structures with extensive calibrations to field data.

Our river survey program includes state-of-the-art satellite and inertial positioning, survey-grade single- and multibeam echosounders, Acoustic Doppler Current Profilers (ADCPs), and real-time data processing to survey bathymetry, velocity, and bed shear stress quantification.

Reduced-scale models of Wanapum, Brownlee, and Hells Canyon dams were constructed to investigate TDG abatement options. Spillway deflectors were designed to reduce air entrainment and TDG by redirecting plunging spillway jets. The original sectional models of each dam were also used to develop discharge rating curves for spillway and sluiceway gates and to investigate tailrace erosion potential.

IIHR's physical models.

IIHR’s physical models.

Reduced-scale models related to fish passage in the Columbia and Snake River Basin included the Wanapum forebay model with fiberglass wicket gates and turbine scroll housings, the Wanapum Dam tailrace model with modeled bedrock layers and full flood flowrate capacity, physical sectional model of Wanapum Dam’s future unit fish bypass facility, the Brownlee Dam 1:50 scale power canal model, the Priest Rapids Dam forebay model including part of Goose Island and fish passage facilities, and the Priest Rapids Dam 1:64 scale comprehensive tailrace model.

Last modified on October 11th, 2016
Posted on March 16th, 2012