Measurement of flow velocity profiles in tank structures using the prototype device OCM Pro LR

Area of Science:

• Environmental Engineering
• Fluid Dynamics
• Wastewater Treatment

Background:

• Wastewater and stormwater treatment efficiency studies often focus on hydraulic loading and internal processes.
• Computational Fluid Dynamics (CFD) modelling and lab tests are common for evaluating internal tank dynamics.
• Understanding flow paths is crucial as they significantly influence treatment efficiency in tank structures.

Purpose of the Study:

• To investigate the applicability of flow velocity profile (FVP) measurements for assessing large-scale tank structures.
• To calibrate CFD models and enhance comprehension of pollutant transport processes.
• To evaluate the performance of the OCM Pro LR prototype device in a real-world setting.

Main Methods:

• Conducted tests using the NIVUS OCM Pro LR prototype FVP measurement device.
• Performed measurements in a sedimentation tank experiencing combined sewer overflow (CSO) in Petange, Luxembourg.
• Utilized ultrasonic signal analysis to determine detailed FVPs and compared results with vane measurements.

Main Results:

• The OCM Pro LR system provided detailed FVPs by analyzing ultrasonic signal echoes across different flow depths.
• Measurements from the OCM Pro LR showed good agreement with traditional vane measurement methods.
• FVPs indicated the presence of shortcut flows within the tank during CSO events, potentially reducing cleaning efficiency.

Conclusions:

• The study demonstrates the practical applicability of FVP measurements in large-scale wastewater treatment structures.
• OCM Pro LR measurements effectively identify flow anomalies like shortcut flows.
• Findings highlight the importance of FVP analysis for optimizing the design and operation of sedimentation tanks.