Independent field testing has verified the in-situ accuracy of Rubicon's SlipMeter™ flow measurement and control device.

In October, California based consulting group Provost and Pritchard tested a 600mm SlipMeter™ installed onto the upstream headwall of the Van De Pol turnout in the Oakdale Irrigation District.

The SlipMeter's™ accuracy was assessed over 18 tests which covered a wide range of operating conditions, representative of those that would be expected for a typical turnout. Testing was conducted at flow rates from 1cfs to 15cfs (2.4 ML/d to 36.7 ML/d).

At flow rates between 3cfs and 12cfs (7.3 ML/d and 29.4 ML/d), the SlipMeter™ was accurate to within ±1% of the reference flow meter. Provost and Pritchard engineers report that the 1cfs tests would likely have been within the ±1% range if these tests had been run for a longer duration to reduce the overall experimental uncertainty.

One test was conducted with a large sheet of form-ply placed at the entry to the SlipMeter™ to create a 75% obstruction of the meter opening. The 3.18% error reported for this test lies within Rubicon's stated measurement accuracy of ±5% in the field, an impressive result given the severe nature of this disturbance.

Provost and Pritchard concluded the SlipMeter™ performed well within its installed configuration, and was consistently accurate to within ±2% of the NIST (National Institute of Standards and Technology) certified reference magmeter.