Q: As you know , there needs to be a minimum of 10 diameter straight pipe length in order to accurately measure the flow rate with an ultrasonic flow meter.
What should one do if there is not long enough straight pipe length ?
Does the lack of long straight pipe mean that an ultrasonic flow meter should not be used ?
Can a correction factor for the flow rate reading be estimated and applied? If yes, does the estimation of correction factor violate IPMVP adherence ?
Thank you for your guidance

A: I would use recommendations from the meter manufacturer for the use of this and any other meter. The accuracy of thsi meter will suffer with fewer upstream diameters downsteam diameters are less critical). There is no reliable correction factor that i know of, the flow will be more turbulent with the lack of straight pipe and readins less reliable.