University of Illinois Urbana-Champaign

Turbulent friction in eccentric annular conduits; effect of inserted pipe on flow capacity of sewers

Robertson, James M.

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https://hdl.handle.net/2142/112035

Description

Title
Turbulent friction in eccentric annular conduits; effect of inserted pipe on flow capacity of sewers
Author(s)
Robertson, James M.
Issue Date
1968-03
Keyword(s)
  • Friction
  • Eccentric Annular Conduits
Abstract
Following a general review of the analytical and experimental information on the friction loss encountered by fluids flowing in annular pipes, with particular regard to the influence of eccentricity of the inner member, experiments are described on an evaluation of the friction of water in a steel annular pipe of diameter ratios 5.8 and 3.2 in the Reynolds number range of 105 to 106. It is found that, on a friction factor basis (in terms of the equivalent diameter as four times the hydraulic radius), whereas at the larger ratio the concentric position of the insert increases the friction only about 2 percent, its full eccentric location results in a decrease of some 15 per cent. On a discharge basis, however, for the same head loss in a given length, the flow capacity of the pipe line is decreased 12.7 per cent in the concentric situation but only 4.5 percent with full eccentricity. This decrease is not greatly different from the 3 percent reduction in area due to the inserted smaller pipe. An analysis is included showing that for the simple insert at full eccentricity the near-full-flow capacity of a sewer is little affected. The effects of hangers such as might be employed to support inserts in sewers is found to have an appreciable effect on the flow capacity of a full-flowing sewer.
Publisher
Department of Theoretical and Applied Mechanics. College of Engineering. University of Illinois at Urbana-Champaign
Series/Report Name or Number
  • TAM R 310
  • 1968-0118
ISSN
0073-5264
Type of Resource
text
Language
eng
Permalink
http://hdl.handle.net/2142/112035
Sponsor(s)/Grant Number(s)
Task 12 of the ASCE Combined Sewer Separation Project, Contract FWPCA No. 14-12-29
Copyright and License Information
Copyright 1968 Board of Trustees of the University of Illinois

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Technical Reports - Theoretical and Applied Mechanics (TAM) PRIMARY
TAM technical reports include manuscripts intended for publication, theses judged to have general interest, notes prepared for short courses, symposia compiled from outstanding undergraduate projects, and reports prepared for research-sponsoring agencies.