Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Civil and Environmental Engineering

Committee Chair(s)

Zachary B. Sharp


Zachary B. Sharp


Michael Johnson


Austin Ball


Accurate flow measurement data is necessary to effectively manage water resources. The purpose of this research is to investigate options to improve field flow measurement by investigating alternatives for calibrating flow meters installed in non-ideal piping. Typically, to accurately measure a flow rate using most types of flow meters, it is recommended that a straight section of pipe be installed immediately upstream and downstream of the flow meter to avoid flow fluctuations at the meter location. However, in many cases, flow disturbances upstream of the meter are unavoidable.

The performance of field flow measurements in non-ideal piping scenarios were studied using physical laboratory experiments and CFD models. Two common flow meter technologies, namely insertion velocity probes and ultrasonic strap-on flow meters were used to measure flow rates downstream of a disturbance in flow for three different pipe installations. The error in flow measurements resulting from the flow disturbances were determined at four locations downstream of the flow disturbance, at three orientations on the circumference of the pipe, and for four flow rates with velocities ranging from 1 ft/s to 10 ft/s. Using the same physical conditions found in the laboratory, numerical models were built and tested to find results. The flow deviation recorded from the CFD model was used as a correction factor for the physical data. The insert probes and ultrasonic flow meters performed less accurately when positioned closer to the flow disturbance due to the turbulent fluctuations and flow separation created by the disturbance.

By applying the correction factor determined from the CFD models, the accuracy of the ultrasonic flow meters in non-ideal piping improved significantly. The results for the insert probe were less clear but did show improvements in most cases. Further CFD modeling efforts could be used to best improve the accuracy of the insert probes. Computational Fluid Dynamics appears to be a viable tool for improving flow meter accuracy in the field. This approach will likely be valuable in other scenarios and will result in more accurate flow measurement and the effective management of water resources.