ESTUARINE CURRENT METER CONTRACT

Abstract

An instrument is being developed for measuring accurately and recording continuously the velocity of the water at a fixed point in an estuary. The instrument must have a range of 0.05 to 3 knots and an accuracy of + or - 0. 05 ft/sec. It should be small and light and have no external moving parts requiring rotating or sliding bearings. The sensing element is to operate at depths of 200 ft. A survey of the literature was made, and 2 methods were studied: (1) a system for measuring the force exerted on a solid body submerged in the flow and (2) a system for measuring the difference in time taken by a sound wave to traverse a fixed distance in the direction of and against the current. The ulrasonic system is being designed to employ 2 crystal transducers separated by a path length of 26 in., which will alternately transmit and receive a 1-mc signal. The estuarine current meter will be attached to an anchor on the bottom of the estuary by a cable system.

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Document Details

Document Type
Technical Report
Publication Date
Jan 31, 1953
Accession Number
AD0004294

Entities

People

  • C. F. Miller

Organizations

  • Johns Hopkins University

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Acoustic Propagation
  • Acoustic Waves
  • Bodies
  • Coefficients
  • Contracts
  • Directives
  • Errors
  • Literature
  • Solid Bodies
  • Sound Waves
  • Specific Gravity
  • Transducers
  • Waves

Readers

  • Coastal and Marine Engineering/Sediment Transport/Hydraulic Engineering
  • Electrical Engineering
  • Oceanography.