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5.4
Selection of the Sound Beam Plane Near an Elbow
On vertical pipes
On horizontal pipes
• The sound beam plane (see section 3.3) has an angle
of 90° to the elbow plane. The elbow is upstream of the
measuring point.
• The sound beam plane (see section 3.3) has an angle
of 90° ±45° to the elbow plane. The elbow is upstream
of the measuring point.
With measurements in both directions
• The sound beam plane (see section 3.3) is selected ac-
cording to the nearest elbow (horizontal or vertical, de-
pending on the pipe orientation - see above).
flow direction
elbow plane
flow direction
flow direction
elbow plane
