Measurement principle of small open channel flow meter

Measuring principle:

This instrument is designed based on the velocity-area method principle for open channel flow measurement. By measuring the flow velocity, the flow rate Q = V·S (S is the cross-sectional area) can be obtained.

1. Flow rate measurement:

When measuring flow velocity, the propeller rotor flowmeter is driven by hydraulic power to rotate, and the built-in signal device generates a rotation signal. The flow velocity is calculated by the following formula:

KN

V＝———————— ＋ C（m/s）

T

Where: V: average flow velocity during the flow measurement period (m/s)

K: hydraulic pitch of propeller blade C: current meter constant

T: flow measurement duration (unit: S) N: number of signals within T period

When the instrument is in use, K and C are both constants. When measuring flow, the flow rate can be calculated by simply measuring T and N.

2. Calculation of flow:

Flow measurement is based on the velocity-area method of open channel flow measurement. The velocity is first measured and then multiplied by the cross-sectional area to obtain the flow rate.