PNNL

Abstract

Natural resource applications of computational fluid dynamics (CFD) models are becoming more frequent with the advances in computational power and the availability of commercial meshing software and verified CFD solver applications. The Bonneville Lock and Dam Project, constructed and operated by the U. S. Army Corps of Engineers, is the westernmost dam on the Columbia River, and is located about 40 miles upstream of Portland, Oregon. A set of 3D CFD models have been developed for the Bonneville Project forebay and turbine intakes; the CFD models provide a tool to predict the impact of proposed changes in operational rules both for the overall river flow patterns and near the turbine intakes. These models also offer rapid insight into the performance of proposed or existing hydraulic structures. The creation of a computational domain for Bonneville was complex and required the use of many software tools to integrate the diverse data sources that described the river and powerhouse geometry into a single computational domain. Once the computational mesh was created, flows were simulated by solving the Reynolds-averaged Navier-Stokes (RANS) equations together with a two-equation (k-epsilon) turbulence model. The model was validated using velocity data measured in reduced scale physical models and in the field.