Open Channel Flow - The use of Level sensors for open channel flow measurement
Level sensors from SolidAT are implemented in Open Channel Flow applications. In these types of applications, the level sensor is installed above a special water flow structure and accurately measures level of flowing water or wastewater. The sensor then calculates flow through the structure using hydrology formulas. Formulas are implemented for structures such as flumes, weirs and open pipes.
Gauger systems, SmartScan50 and MonoScan all measure level in open channels and can calculate flow. Level to Flow conversion equations for flumes and weirs are a part the firmware for each of these devices. Popular flumes and weirs are supported:
European and American standards are both supported. SmartScan50 and MonoScan can be configured for m3/h and GPM units. Gauger can be configured for m3/h, cf/s, GPM, l/s and MGD units. An Excel calculator for Open Channel Flow can be downloaded from SolidAT web-site. Download the Excel calculator for OCF in flumes, weirs & Manning.
SmartScan50 systems should be used when these additional features are required:
- Totalization (accumulated flow)
- 5 relays including totalization counter (pulses per flow)
- 2-part system with the display at a distance from the measured wastewater
- Measuring flow in custom canals (by use of a strapping table)
- General canal, channel, ditch and open pipe flows (Manning formula)
- Remote sites requiring wireless (GSM) reporting
- Remote sites requiring battery based operations
- Other types of flumes and weirs and additional unit types
Why measure wastewater flow?
Wastewater flowing through channels relates to cost and environment protection. Water purification plants may get paid based on wastewater quantities. Manufacturing plants may pay for the amount of effluent that the plant pours out. Municipalities may want to measure amount of wastewater running through their sewer systems to prevent wastewater leakage and check pipe overstressing.
What is open channel flow?
Open Channel Flow (OCF) is flow driven by gravity and exposed. OCF refers to water and wastewater. Water flow is found in agricultural distribution networks. Wastewater flow is found in municipal sewer systems and water purification plants. Measuring flow in open channels is obtained by routing the liquid through special structures, flumes or weirs and using an hydrological or empirical equation to convert level to flow.
Why non-contact technology and why Ultrasonic level sensors?
Wastewater cannot be measured efficiently by traditional contact sensors (float, capacitance, bubblers etc.). With contact sensors, waste sticks and tampers with the device performance. Non-contact measurement is the only practical method. Ultrasonic level measurement is non-contact, cost effective safe and preferred to expensive Radar technology. Traditional flow meters for closed pipes are based on the liquid filling the cross section of the pipe which is not the case in OCF.