Vittorio BOVOLIN | Environmental and Maritime Hydraulics Laboratory

Presentation

The Environmental and Maritime Hydraulics Laboratory (LIDAM), University of Salerno, completed in July 2004, covers an area of approximately 1000 mq of which approximately 800 mq are occupied by a plant which partly houses educational equipment to support hydraulic-based B.Sc./M.Sc./Ph.D courses, partly taken by experimental equipment used for scientific purposes. Since the second semester of the academic year 2004/2005, LIDAM supported teaching activities whereas since 2003 research has been carried out, either as indoor activities and for external environmental monitoring.

Equipment

The laboratory hosts didactic equipment to support the hydraulic-based B.Sc./M.Sc./Ph.D courses, as well as experimental equipment used for scientific purposes.

Experimental equipment used for scientific purposes

• Channel for the study of debris flows.

Large-sized, moved by hydraulic pistons and equipped with a "rotating cavity" pump capable of lifting mud in a "non-impulsive" way.

Technical specifications.

1. Length: 8 m
2. Width range (adjustable): 10 cm - 80 cm
3. Depth of flume 90 cm
4. Slope angles 0° (horizontal) -25° (steep slope)
5. Plexiglas side walls and transparent basal surface for non-intrusive optical observations.
6. Gate (width: 24 cm, height: 90 cm) with spring-based rapid opening system to reproduce dam break conditions (opening time: <0.1 s).
7. Recirculating system, based on a Archimedes screw (Sydex LK-130).

Allows the analysis under steady-flow conditions.

Maximum discharge (clear water): 50 l/s

Maximum Head: 5 bar

Maximum size of solid particles: 12 mm

Inverter: Siemens Micromaster 440

Upstream tank: ≈3 mc

Downstream tank equipped with mixing engine: ≈4 mc

• Channel system to study the propagation of granular mixtures

Small-sized, aimed at better understanding potentially dangerous natural phenomena such as rock avalanches and debris flows. This system is equipped with two high-speed cameras, with a recording capacity of up to 10,000 frames per second, to measure velocity and concentration profiles in granular mixtures. The video recording system is completed with a controlled brightness lighting system based on lamps with LED technology. The apparatus was financed by the University Large and Medium Equipment fund (Year 2006).

Technical specifications.

1. Length: 2 m
2. Width: 8 cm
3. Channel depth: 20 cm
4. Slope angles 0° (horizontal) -50° (steep slope)
5. Plexiglas side walls for non-intrusive optical observations.
6. Gate (width: 8 cm, height: 20 cm) with spring-based rapid opening system to reproduce dam break conditions (opening time: <0.1 s).
7. Bottom adjustable with different surfaces smooth to rough.
8. Feeding hopper to establish nearly steady-state granular flow conditions.
9. Mass flow rate range: 0-3 kg/s.
10. Measurements of velocity and concentration profiles at lateral walls in dry granular flows by means of: two high-speed digital cameras (mod. AOS S-PRI with a max. sampling rate of 1.2 KHz and AOS Q-PRI with a max. sampling rate of 10 KHz) two high-intensity flickering-free planar LED lamps (mod. Photo-Sonics MultiLED-LT, ≈8000 lumen); 1 Load cell (mod. LaumasAZL-50kg) with resolution of 1g and accuracy of ≈0.08g; Laser: Laser Components FlexPoint mod. FP-MV micro-660-100D-45-F-TS-12V (wave length 660nm, dimmable power 0-100mW, fan angle of the laser sheet 45°, focusable).

• Electro-mechanical channel system for the study of viscous flows induced bottom shear stress

Small-sized, aimed to measure the bed shear stress exerted by a channelized viscous flow. This system is equipped with a high-speed camera, with a recording capacity of up to 1200 frames per second, for the measure of the velocity profile. The apparatus was financed by C.U.G.RI. (interUniversity Centre for the Prediction and Prevention of Major Hazards) Equipment fund (Year 2006).

Technical specifications.

1. Length: 2 m
2. Width: 30 cm
3. Channel depth: 30 cm
4. Slope angles 0.8° – 45° (steep slope) adjustable by means of an aluminum frame equipped with blocking hinges.
5. Plexiglas side walls for non-intrusive optical observations.
6. Bottom adjustable with different surfaces smooth to rough.
7. Flow rate recirculation system to ensure steady state conditions.
8. Gate (width: 30 cm, height: 30 cm) with manual opening system (handle on the front side) to reproduce dam break conditions (opening time: <0.3 s).
9. Flow rate range: 0-2 l/s.
10. Measurements of viscous flows velocity profiles at lateral walls by means of: a high-speed digital camera (mod. AOS S-PRI with a max. sampling rate of 1.2 KHz).

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• Electro-mechanical system for the experimental investigation of a hydraulic ram.

Small-medium size (adjustable delivery), aimed at studying the pumping efficiency of a hydraulic ram. National Instruments® (NI) DAQ sampling system with conditioning system and analog-to-digital conversion system (ADC).

Pressure detection with:

1. 2 piezoresistive transmitters mod. TRAFAG 123863
2. Sensor: Ceramic: Pressure range: 0 ... 250 mbar; Accuracy: ± 0.1%, Out: 0 ... 50mV; In: 10 V DC;
3. 2 strain gage transmitters mod. TRAFAG 8253: Sensor: Thin film on steel; Pressure range: 0 ... 2.5 bar; Accuracy: ± 0.1%; Out: 0.5 ... 4.5 V; In: 5 V DC;
4. NI-cDAQ-9274 acquisition module with timing control, synchronization and I/O transfering;
5. NI-9218 analog input module with frequency sampling rate: 51.2 kS / s / ch, compatible with TRAFAG 123863 sensor;
6. NI-9220 voltage input module with frequency sampling rate: 100 kS / s / ch compatible with TRAFAG 8253 sensor.

• Pilot plant for energy harvesting from falling water in drainpipe

Middle-sized. Pilot plant for the assessment of energy harvested from falling water in drainpipe tank. Components:

1. 60 l storage tank connected to a pressurized system
2. PVC pipe. Diameter: 80 mm, length: 4.20 m
3. Pelton micro-turbine connected to a 12V generator
4. Adjustable Pelton blades (PLA, ABC printed)
5. 12V battery for energy storage
6. water jet produced by a nozzle of adjustable diameter (3 to 7 mm).
7. Lower system (Pelton, generator, battery, containing plexiglas tank) detachable to be shown outdoor for educational purposes.

• Pilot plant for the assessment of filter cartridges filtration for domestic water treatment

Middle-sized. Pilot plant for the efficiency assessment of filtering cartridges for domestic water.

1. Feeding/recirculation tank, size: 300 l, connection DN 1” e ¾”
2. Single-phase pump, mod. Calpeda NMM-1/AE, Flow rate min/max 1 – 4.2 mc/h, Head min/max 16.3 - 22 m
3. Volumetric flow rate B Meters
4. Plastic holder for filtering cartridges, manufacturer Acqua Brevetti, Italy.
5. Filtering cartridges of various types. Diameter: 61 mm, height: 250mm.
6. Differential pressure gauge, mod. Digitron Engineering B.V. 2082P, range: 0-7 bar

Educational equipment:

• Test bench for the study of pipeline flows under steady state conditions

Made of a vertical panel, 12 m long and 2 m high, covered with Bakelite sheets, on which the pipes were subsequently fixed. On one side of the bench, there are a series of pipes of different diameters; on the other side, two plexiglas tanks were installed at the ends, connected with two pipes, in parallel. The pipes are equipped with piezometers and a series of valves, open / closed, which allow it to reproduce various types of problems.

• tilting channel for the study of free surface flows under steady state conditions

20 x 40 cm rectangular cross section; total length: 6 m. Hinged at one end to vary channel slope between 5% to a counter slope of 1%; the inclination of the canal is modified thanks to a special demultiplier.

• Wind tunnel for the study of the interaction between gas flows and objects

Provided with a central test section made of Plexiglas, with a section of 30 x 30 cm and 1 m long, equipped with a lateral hatch that allows to insert both flow measuring instruments and profiles on which to observe the pressure trend.

• Test bench for the study of mass oscillation.

Made of an iron frame structure on which a still tank is laid, a steel pipe circuit, piezometers, an air tank, a lower supply tank and a pump; immediately downstream of the pump there is an air tank, made with a plexiglas cylinder which in case of shutdown of the feeding system shows the oscillation of the water level.

The equipment above described is completed with a series of electronic instruments to support both teaching and research.

The mission of the Environmental and Maritime Hydraulics Laboratory (LIDAM) is to provide services for teaching and research in the fields of Hydraulic Engineering and Fluid Mechanics. We believe that working with real motion of fluids brings enormous benefits for an efficient education in the fields of the Hydraulics.

In the Laboratory, Researchers as well as BSc, MSc and PhD Students can carry on experimental tests and physical modelling aimed at characterizing either pressurized or free surface flows. Experimental set-ups and apparatus are regularly designed, built and maintained or dismantled according to current needs.

Measurements are performed according to the UNISA and the national standards (D.M. 363/1998, T.U. 81/2008), to ensure the safety of the students as well as the staff involved.

Outdoor activities are foreseen as well, performing field measurement campaigns as well as river/sea state monitoring …