Operation & Maintenance

How to Maintain an RBC Flume

For proper flow measurement, RBC flumes require periodic inspection.

This inspection should include the flume's channel, the flow entering / exiting the flume, and the flume itself.

Channel Inspection

• The upstream channel banks should be clear of vegetation or debris that could affect the flow profile entering the flume (upstream) or restrict flow out of the flume (downstream).
• Inspect the upstream channel to make sure that flow is not bypassing the flume.
• Inspect the downstream channel to make sure that scouring is not occurring.
• Any hydraulic jump should be at least 30 times the maximum head (H_max) upstream of the flume.

Flow Inspection

• Flow entering the flume should be tranquil and well distributed.
• Turbulence, poor velocity profile, or surging should not be present.
• The Froude (F_r) number should, ideally, be 0.5.
• As the Froude number increases so does surface turbulence.
• Flumes accelerate sub-critical flow (F_r < 1) to a supercritical state (F_r 1>) .
• Flumes experiencing flows greater than unit (F_r = 1) will not accurately measure flow.

Flume Direction

• For first time inspections, make sure the flume is installed facing the right way.
• The ramp of the flume must be downstream.

Flume Inspection

• Flumes must be level from front-to-back and from side-to-side.
• Earthen installations are particularly susceptible to settling due to wet / dry and freeze / thaw cycles.
• Flow surfaces are to be kept clean of surface buildup or algal growth. Scrubbing or a mild detergent can be used.

Galvanized Specific Maintenance

• Check for corrosion.
• Any corrosion should be removed, the area dried, and then cold galvanization applied.