Flow measurement
Knowing the flow and volume?
To determine the flow in fully or partially filled pipes and open channels, different measurement methods can be used. For flow volume regulation, volume calculations, penstock monitoring or turbine efficiency measurements, Rittmeyer offers the right solution for each application. The flow can thereby be measured directly by means of ultrasonic transit time measurements or indirectly by measuring the differential pressure or the water level.
Ultrasonic transit time measurement
With its modular design, the RISONIC modular system offers flexible measurement applications, cost-efficiency as well as maintenance-free long-term stability and reproducible results even in harsh environments. For flow measurements in both directions, customers can choose between firmly mountable and non-invasive, i.e. magnetically mountable sensors. Furthermore, the analysis of the signal quality enables the detection of suspended solids in the water. Thanks to the extremely high measurement accuracy, measurement values can also be used to determine turbine efficiency.
Advantages of this method
- Wide range of pipe diameters: up to 35 meters
- High accuracy class: up to 0.5% if used on-site and 0.2% in the lab
- Easy to retrofit even with existing third party sensors
- Comprehensive remote diagnostics and control through modern communication interfaces
- Enables continuous monitoring of penstock integrity, amount of suspended solids, and turbine efficiency
Flow measurement using the differential pressure method (Winter-Kennedy)
A constriction of the pipe cross-section, e.g. near a turbine, increases the speed and causes a pressure drop. The differential pressure is determined with RIPRESS smart. The flow rate is then calculated based on that measurement using a mathematical function or reference table.
Advantages of this method
- Commonly used method in hydraulic engineering
- Costs are largely independent of the pipe diameter
Flow measurement through level measurement (formed spillway)
For open channels, the flow can be determined using a level measurement in geometrically defined spillway shapes, e.g. using the pressure, ultrasonic, float or radar method. Based on the level, the flow rate can be calculated using a predefined function or reference table.
Advantages of this method
- Easy to install
- Very robust
- Cost-effective