Vacuum Tank Tests of Model Tainter Valve for McNary Dam
Abstract
McNary Dam, one unit in the comprehensive development of the Columbia and Snake Rivers in Oregon, consists of a gate-controlled spillway of twenty-two 50-ft bays, a powerhouse for fourteen 95,400-hp turbine generator units, a single-lift navigation lock 86 by 675 ft with approach guide walls, facilities for migrating fish, and two earth-fill abutments. Total length of the project is approximately 7,300 ft; average head is 85 ft. It is proposed to use a tainter valve to control flow through the lock culvert at McNary Dam. Model tests of the culvert and valve were conducted under atmospheric conditions at the Bonneville Hydraulic Laboratory, CE, Bonneville, Oregon. These teats revealed negative pressures dangerously near the cavitation range in the culvert immediately downstream from the tainter valve. Since the Waterways Experiment Station had available a vacuum tank, the District Engineer, Portland District, requested that tests be conducted therein to determine whether cavitation actually would occur below the valve. This report presents the results of those tests.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1949
- Accession Number
- ADA637747