DIN EN ISO 748 E : 2008
Current
The latest, up-to-date edition.
Hardcopy , PDF
English
01-01-2008
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Principle of the methods of measurements
5 Selection and demarcation of site
5.1 Selection of site
5.2 Demarcation of site
6 Measurement of cross-sectional area
6.1 General
6.2 Measurement of width
6.3 Measurement of depth
7 Measurement of velocity
7.1 Measurement of velocity using current-meters
7.1.1 Rotating-element current-meters
7.1.2 Electromagnetic current-meters
7.1.3 Measurement procedure
7.1.4 Oblique flow
7.1.5 Determination of the mean velocity in a vertical
7.1.6 Errors and limitations
7.2 Measurement of velocity using floats
7.2.1 General
7.2.2 Selection of site
7.2.3 Measuring procedure
7.2.4 Types of float
7.2.5 Determination of velocity
7.2.6 Main sources of error
8 Computation of discharge
8.1 General
8.2 Graphical method
8.2.1 Depth-velocity-integration
8.2.2 Velocity-area Integration method
(velocity-contour method)
8.3 Arithmetic methods
8.3.1 Mean-section method
8.3.2 Mid-section method
8.4 Independent vertical method
8.5 Mean-section method - Horizontal planes
8.6 Determination of discharge from surface-float
velocity measurements
8.7 Determination of discharge for variations of
water level
8.7.1 General
8.7.2 Computation of discharge
8.7.3 Computation of mean water level
9 Uncertainties in flow measurement
9.1 General
9.2 Definition of uncertainty
9.3 Method of calculating the uncertainty in
discharge by measurement of velocity by
current-meter
9.3.1 General
9.3.2 Contributory uncertainties
9.3.3 Example
9.3.4 Combined uncertainty
9.4 Method of calculating the uncertainty in discharge
by measurement of velocity using floats
9.4.1 General
9.4.2 Contributory uncertainties
9.4.3 Combined uncertainty in discharge
9.4.4 Example
Annex A (informative) Correction for sag, pull, slope and
temperature in measurement of cross-section
width by tape or wire
Annex B (informative) Distance measurement across the
cross-section
Annex C (informative) Corrections for wetted length of wire
when measuring depths with wire not
normal to surface
Annex D (informative) Correction for drift
Annex E (informative) Uncertainties in the velocity-
area measurement
Annex F (informative) Determination of mean velocity
from float measurements
Bibliography
National Annex NA (informative) Bibliography
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