CNR-INM | Consiglio Nazionale delle Ricerche | Istituto di Ingegneria del Mare
+39 06 50299 222

Hydraulic channel


The Hydraulic Channel @INM is a classical, recirculating-type, open channel flume. Its huge working length (27 m) makes it particularly suited to replicate environmental flows where horizontal length scales are much larger than the vertical one (e.g., shallow water phenomena occurring in rivers or coastal areas) or to study the propagation and breaking of surface waves. However, it can also be used much like a standard (namely, closed section) channel in order to investigate a wider class of fluid dynamics phenomena: shear – or wall- turbulence, multiphase flows (sedimentation of heavt particles, or dynamics of air bubbles), biological fluid-dynamics problems and so on.

When the facility is operated, the water is displaced by three 22 hp pumps from a 27 cubic meter reservoir through a reinforced PVC pipe, up to an height of 3.5 m. From here, it flows through a settling chamber, a series of conditioning elements (honeycombs and grids) and a 3.5:1 contraction, before eventually entering the test section. Here, the water velocity can be varied up to 1 m/s by means of the variable frequency controller which drives the pumps. The test section is 27 m long, 0.6 m wide and 0.75 m deep. It terminates with a variable height, sharp-crested weir. The vertical sides are entirely constructed from toughened glass panels to allow flow visualization and use of Laser Doppler – or other optical velocimetry techniques. The bottom is made of stainless steel, except for two transparent acrylic panels for optical access (each 1 m long). The entire structure is supported by a steel frame and rests on two hydraulic jacks, so that the flume can be tilted from a 0° to 3°.

Standard instrumentation includes standard – and subminiature multi-component Pitot tubes, Acoustic Doppler Velocimetry, free-surface elevation gauges, hot-film anemometry. Optical velocimetry (2- or 3-D Particle Image Velocimetry, Defocusing PIV, Laser DopplerAnemometry) can also be supplied.

Main characteristics

Test section length 27 m
Cross-section dimensions 0.6 m X 0.75 m
Maximum water speed 1 m/s
The Hydraulic Channel @INM
(as viewed from the outlet section)

Contact information

Scientific point of contact Boris F. Jacob
+39 06 50299 229


Rome HQVia di Vallerano 139, 00128, Rome, Italy