Accession Number:

ADA038051

Title:

Flow Conditions at Pumping Stations, Cairo, Illinois; Hydraulic Model Investigation.

Descriptive Note:

Final rept. Mar-Nov 75,

Corporate Author:

ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MISS

Report Date:

1977-03-01

Pagination or Media Count:

67.0

Abstract:

The model study reported herein was conducted to evaluate the characteristics of inflow to the original design sump and to develop modifications required for improving the distribution of flow to the pump intakes. The study indicated the need for certain minor modifications to improve flow characteristics in the forebay and ensure satisfactory flow characteristics and pressures near the pump intakes. The major problems encountered were generated by the concentrated, submerged jet entering and passing through the forebay. The concentrated jet emerging from the approach conduit into the forebay produced adverse currents and turbulence near the pump intakes. Satisfactory approach flows were obtained by installing 6-ft-high baffles in the forebay and rounded pier noses at the entrance to the individual pump bays. The baffles were effective in dispersing the jet entering the forebay and the rounded pier noses eliminated the instability and separation of flow at the entrance to the pump bays. The improved flow distribution eliminated the vapor cavity and certain potential for cavitation damage in the pump intakes. The recommended design provided satisfactory flow performance with all combinations of pump operation and anticipated sump elevations. Maximum pressure fluctuations were reduced from about 32 ft of water with the original design to about 5 ft water with the recommended design. Author

Subject Categories:

  • Civil Engineering

Distribution Statement:

APPROVED FOR PUBLIC RELEASE