KATflow 200 – Reliable Flow Measurements in Turbulent Environments

When withdrawing water from watercourses, hydroelectric power plants are subject to established maximum limits required to generate a specific amount of electricity. As the plant ages, it becomes increasingly difficult to accurately determine these maximum withdrawal volumes when the original plant parameters (e.g., pumping capacity) change due to the plant’s aging. In summary, this usually results in reduced efficiency. In particular, aging hydroelectric power plants require a higher water flow rate to generate a specific amount of energy.

Katronics’ Italian distribution partner, Selemark, was approached at a trade show by an engineer from a power plant group. The engineer explained that the turbines in the group’s hydroelectric power plants have been in operation since the 1950s and that, due to the higher water flow required to meet generation targets, the plants now risk losing their permits. In preparation for a planned renovation, the customer needed a flow measurement solution that could be implemented without interrupting power generation—that is, while the process was still running.

Katronic’s portable ultrasonic flowmeter, the KATflow 200, equipped with compact K1 sensors, was used for the feasibility study subsequently initiated. The sensors were mounted on the pipe using coupling paste and metal chains. The Acoustic Sensor Positioning Assistant, which is supported by all Katronics ultrasonic flow meters, enables the user to mount the transducers on pipes quickly, effortlessly, and precisely, allowing measurements to begin immediately with the best possible signal strength.

The outdoor iron pipes installed at this hydroelectric power plant have a diameter of 650 mm and run uphill at a typical angle of 27°. The mountainous terrain led to a projected ambient temperature range of -20 °C to +35 °C. Due to the heavy rust buildup found on site, the roughness of the pipe’s inner surface was estimated to be up to 4 mm. The flow rate through the pipes is typically 1.0 m^³/s, and the customer wanted the most accurate flow measurement possible, along with a reliable alarm that would trigger as soon as the flow rate exceeded the withdrawal limit of 1.5 m³/s.

The anticipated amount of rust on the inside of the pipeline and a predicted flow velocity between 3.1 and 4.9 m/s suggested higher turbulence and, consequently, significant noise in the measurement signal. The KATflow 200’s advanced signal processing perfectly compensated for both factors. The flow rate measurement stabilized immediately and delivered excellent results. A customer engineer was able to confirm Katronic’s ultrasonic flow measurements on-site by observing the simultaneous variation in flow rate within the known percentage range and verifying the meter’s performance.

In this application, Katronic enabled a group of small hydroelectric power plants in Italy to remain within their permitted withdrawal limits. The KATflow 200, a non-invasive, portable clamp-on flow meter that is easy to install on cast-iron intake pipes, provided a first-class solution for reliably and accurately measuring the water flow into the generator set during normal power plant operation.

Following this successful trial, the utility is expected to purchase up to 30 KATflow flow meters for the project, which is scheduled to be completed within one year.

Image credit: Selemark