A clamp-on flow-monitoring system from Cidra Corp., Wallingford, Conn. (www.cidra.com), uses an acoustic array and sonar technology to accurately calculate single and multiphase flows, including slurry flows, inside pipes. The array, mounted on the outside of the pipe, detects pressure fields generated by flow in the pipe. The device applies algorithms that let it determine the speeds of turbulent eddies inherent in virtually all industrial process flows. Flow rates are calculated directly from the speed profiles.
If a two-component mixture is flowing in the pipe, and assuming the user knows the speed of sound through both components, Sonartrac will determine the percentage of each in the mixture. This also works in determining how much air is entrained in a solution.
The device requires little in terms of installation, and mounting it outside the pipe eliminates the risk of leaks, pressure drops, clogging and obstructing the flow. It works on pipes ranging from 1 to 60 in. in diameter, flows from 3 to 30 fps in either direction, temperatures to 185°F, and with an accuracy of 0.5% or less.