Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Applications
4.1 Open channels
4.2 Multiple channels
4.3 Closed conduits
5 Method of measurement
5.1 Discharge
5.2 Calculation of discharge from the transit-time
measurement
6 Flow velocity determination by the ultrasonic (transit
time) method
6.1 Principle
6.2 Sound propagation in water
7 Gauge configuration
7.1 General
7.2 Single-path systems
7.3 Multi-path systems
7.4 Crossed path systems
7.5 Reflected-path systems
7.6 Systems using transponders
7.7 Systems using divided cross-sections
7.8 Sloping paths
8 Calculation of discharge
8.1 Single-path systems
8.2 Multi-path systems
8.3 Systems with transducers in the channel
9 System calibration
9.1 General
9.2 Single-path systems
10 Site selection
10.1 Practical constraints
10.2 Physical constraints of the measurement site
10.3 Physical constraints which are distant from the
measurement site
11 Site survey - Before design and construction
11.1 General
11.2 Visual survey
11.3 Survey of the cross-section
11.4 Survey of velocity distribution
11.5 Survey of signal propagation
11.6 Other survey activities
12 Operational measurement requirements
12.1 General
12.2 Basic components of flow determination
12.3 Water velocity determination
12.4 Determination of water stage or depth
12.5 Channel width
13 Gauging station equipment
13.1 General
13.2 Design and construction of equipment
13.3 Reflectors
13.4 Civil engineering works
13.5 Signal timing and processing
13.6 System self-checking
13.7 Site-specific data (or site parameters)
13.8 Clock and calendar
13.9 System performance criteria
13.10 System output
13.11 Installation
13.12 Commissioning
13.13 Operating manual
13.14 Maintenance
14 Measurement uncertainties
14.1 General
14.2 Definition of uncertainty
14.3 Uncertainty in discharge
Bibliography