Foreword

Foreword

1Scope

2Normative references

3Terms and definitions

4Symbols and abbreviated terms

5Principle

6Installation

6.1General

6.2Selection of site

7Measurement of end depth

7.1General

7.2Head measuring devices

7.3Gauge datum

8Maintenance

8.1General

8.2Types

8.3Specifications for the drop structure

8.4Specifications for installation

8.5Determination of gauge zero

8.6Discharge relationship

8.7Coefficient of discharge

8.7.1Confined nappe

8.7.2Unconfined nappe

8.8Practical limitations

8.9Uncertainty of measurement

9Triangular channel drop structure

9.1Specifications for the drop structure

9.2Specifications for installation

9.3Specifications for head measurement

9.3.1General

9.3.2Determination of channel angle

9.3.3Determination of gauge zero

9.4Discharge formula — Unconfined

9.5Practical limitations

9.6Uncertainty of measurement

10Trapezoidal channel drop structure

10.1Specifications for the drop structure

10.2Specifications for head measurement

10.2.1General

10.2.2Determination of gauge zero

10.3Discharge formula — Unconfined

10.4Practical limitations

10.5Uncertainty of measurement

11Circular channel drop structure

11.1Specifications for the drop structure

11.2Specifications for head measurement

11.2.1General

11.2.2Determination of gauge zero

11.3Discharge formula — Unconfined

11.4Practical limitations

11.5Uncertainty of measurement

12Parabolic channel drop structure

12.1Specifications for the drop structure

12.2Specifications for head measurement

12.2.1General

12.2.2Geometry

12.2.3Determination of gauge zero

12.3Discharge formula — Unconfined

12.4Practical limitations

13Uncertainties of flow measurement

13.1General

13.2Sources of error

13.3Kinds of error

13.4Uncertainties in coefficient values

13.5Uncertainties in measurements made by the user

13.6Combination of uncertainties to give total uncertainty on discharge

13.7Example

Bibliography