flow rate measurement

[ren_]

I have 110mm pipe that is receiving outlet wastewater from a treatment system. the flow is continuous but can be zero at times but mostly continuous, It varies constantly diurnal mainly and is very low. I am looking for an alternative way to measure the flow rate of water from the pipe without the use of a flow metre.

 

[LittleInch]

The other way maybe is to build a wall or insert a sealed plate and have a meter in a small bore pipe below water level which connects the two halfs together. A mag flow might be good there or something with no moving parts or things to get obstructed, but at least the meter would be fully submerged all the time.

e.g.

http://www.omega.co.uk/prodinfo/magnetic-flow-meters.html

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[hydtools]

http://www.rissyplastics.com/rissy-products/flout-systems/for-the-designer/flout-flow-rates.html

Here is outflow flow rate chart from Rissy.

Ted

 

[danw2]

Install an on-off valve on the outlet. Close the valve, let the volume fill in whatever you call the container. Measure the level, open the valve at a fixed upper level.

The upper level defines a known volume. Count the number of 'empty' operations, multiply that number of empties by known volume to get total volume.

The error is the in-flow during an empty process, which is not part of the volume when the empty is initiated.

 

[hydtools]

http://www.rissyplastics.com/drawings/4-inch-flout-flow-rates.pdf

FYI

For a draw down of 17 inches(.43m) the average flow rate for a 4-inch outlet is 140 gpm (.0089m^3/sec).

Ted

 

[ren_]

Guys thank you so much for all the responses, suggestions and chipping in, I appreciate all the effort it makes the load lighter