BS 3680-3E:1993

Committees responsible
National foreword
Section 1: General
1.1 Scope
1.2 Normative references
1.3 Definitions
1.4 Units of measurement
Section 2: Method of measurement
2.1 Principle
2.2 Characteristics of sound propagation in water
2.3 Application
2.4 Gauge configuration
2.5 Site selection
2.6 Site survey
2.7 Operational measurement requirements
2.8 Computational requirements
2.9 Concept of measurement redundancy
2.10 System calibration
2.11 Measurement uncertainties
Section 3: Gauging station
3.1 General
3.2 Design and construction of equipment
3.3 System output
3.4 Installation
3.5 Commissioning
3.6 Operating manual
3.7 Maintenance
Annex
A (normative) Determination of flow direction from
      data derived from crossed paths
Tables
1 Systematic errors incurred if the assumed
      direction of flow is not parallel to the channel
      axis
2 Speed of sound in water at different temperatures
3 Sound frequency versus path length and clearance
4 Examples of observed coefficients of velocity
      Cv(= v/vL) for values of d/D between 0,1 and 0,9
Figures
1 Plan of crossed path gauge
2 Plan of reflected path gauge
3 Example of flow calculation by mid-section method
4 Typical relation between velocity coefficient
      K = v/vL and stage
5 Sample curve of d/D values against mean values of
      Cv based upon data from table 4
6 Flat reflector showing effect of temperature
      gradients
7 Layout of gauge using angular reflector
8 Detail of angular reflector
A.1 Plan of cross path gauge

Establishment and operation of an ultrasonic (acoustic) gauging station on a river or open channel. Principles of the method; site selection, design and construction; calibration; operation; uncertainties in measurement.