Arkon parshall flumes’ function is based on the assumption that the critical flow is produced by constricting the width in the throat of the flume and then raising the bottom. The flow changes from subcritical to supercritical and then the measurement of a single depth is sufficient to determine the discharge. The water level is measured and recorded either in the center line of the approach channel using an ultrasonic level sensor or inside a stilling manhole (which can be part of the parshall flume) by means of a float with a mechanical transfer to a flow rate, or using a sensor with an electronic unit. The electronic unit transforms the measured flow depth to a flow rate. Arkon parshall flumes are made of polypropylene and are resistant to air temperatures up to 80 C (however, water inside the flume must not get frozen). Moreover, Arkon parshall flumes can stand well the solutions of inorganic salts, acids and bases that do not exhibit strong oxidation properties, and a majority of organic solvents. Maximum size of suspended solids is limited to 80% of the throat width (dmax = 0.8 w). Arkon Flow Systems also provides checking of your hydraulic projects of parshall flumes at no cost, hydraulic calculation of parshall flumes installations and electronic flowmeters with ultrasonic transducer on request.
Parshall Flume:
