GVF-1
FLUID VISUALISATION UNIT – BASIC HYDRAULIC EDUCATIONAL BENCH
This educational unit has been designed to study, evaluate and measure the basic phenomena and parameters occurring in the study of hydraulics for vocational and experimental purposes. A wide range of testing tubes and devices can be connected to the basic bench with the result of a flexible and modular educational tool that can be supplied in a basic arrangement or can be upgraded progressively up to a complete computer assisted data acquisition and experiment processing system. The G.V.F./1 Fluid-Flow Dynamic Phenomena Visualising Unit enables practical tests on range of instruments generally used in fluid dynamics for measuring flow, pressure, head and for visualising directly certain physical phenomena, such as vortices, frictions, head losses in pipes, Basic hydraulic bench with accessories static head, etc., which are for more easily understood by a practical and direct vision of the phenomenon. The reason lays partly in the objective difficulty of the matter and partly in the lack, up to now, of an appropriate instrumentation allowing to approach and "to see for oneself" the reality of observation. BASIC HYDRAULIC BENCH The bench assembly essentially consists of the following components parts: ¾ Mobile base running on castors. Fabricated from steel sections on which the pump unit support, the flow meter and the feed tank are mounted. ¾ Fluid drop basin. Installed on the assembly base it has the function of preventing eventual water leakage from coming into contact with the electrical equipment. ¾ Circulating centrifugal pump, 50 litres/min. flow rate and 32 meter head height. ¾ Feed tank. ¾ Flow rate meter. It is a rotameter calibrated from 500 to 6000 litres/minute for indicating the instant flow rate can be compared to that measured by means of Venturi meters and orifice nozzles, while the theoretical necessary correlation are taken from it. ¾ Fast joint couplings on the delivery line and at the main tank inlet for test devices installation ¾ Detachable reflecting screen. It is fitted with a mobile flood light provided with a proper screen on which the fluid flows can be visualized. ¾ Mobile carrier with laminar beam lights: it has a function of visualizing the vortices turning out in the ducts owing to sharp variations in the duct diameter. It is essential for making evident the difference existing between laminar and turbulent fluid flows in different parts of the duct itself. ¾ Support screen for measuring instruments. It is a panel suitable for mounting measuring instruments as currently used for flow rate and head tests. The manometers are interchangeable according to the proper flow dynamics circuit used. The assembly also includes: register and on-off valve on the feed and discharge line, pump by-pass circuit with valve. On the suction of the pump it is fitted a regulator for the injection of atomized air, through which it is possible to give in a quantity of air bubbles as desired. This allows the vortices and the fluid vein detachment to be visualized, and the lighting system provides for making this phenomena become more evident in details. ¾ Electric control board for pump operation including main switch, pump switch with warning light, continuous speed regulator for the pump electric motor, wattmeter for tests of power absorption in different operational conditions (optional). I - 16153 P.D. da Bissone 36r. GENOA - ITALY - Tel.: +39 010 6501969 Fax: +39 010 6501969 e-mail: patrone@ giacomopatrone.com http://www.giacomopatrone.com
1
GVF-1
他
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
Instruments included as standard are: two different length differential manometers, suction and delivery manometers at inlet and outlet of the pump (for centrifugal pump investigation). Vacuum meter for ejector tests, instant flow meter.
STEEL BASE FRAME MOUNTING PANEL FOR EXPERIMENTAL PIPES CIRCULATING PUMP WATER FLOW REGULATION VALVE FLOW METER REFLECTOR LAMP MOBILE TROLLEY SCREEN FAST JOINT COUPLING FOR EXPERIMENTAL PIPES TROLLEY SLIDE BY PASS VALVE FOR FLOW RATE ADJUSTMENT Dimensions and weight (gross, wooden case) Meters 2,2x1,2xH2,1 Kg. 450
12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24.
ELECTRIC CONTROL BOARD PUMP ON SWITCH MAIN ON WARNING LAMP PUMP ON WARNING LAMP ELECTRONIC SPEED REGULATOR FOR PUMP MOTOR MAIN SWITCH LOCKER FOR PIPES STORING AIR BUBBLES INJECTION REGULATOR DRAIN VALVE OF FEED WATER TANK FEED WATER TANK LOW VOLTAGE CURRENT TAP FOR REFLECTOR LAMP TRAY DRIP DRAIN PIPE FOR WATER DRIPPING
I - 16153 P.D. da Bissone 36r. GENOA - ITALY - Tel.: +39 010 6501969 Fax: +39 010 6501969 e-mail: patrone@ giacomopatrone.com http://www.giacomopatrone.com
2
GVF-1
MEASUREMENT AND VISUALIZATION MEANS IN PLEXIGLASS A number of 11 different measurement and visualizing instruments can be furnished and chosen with the basic hydraulic bench. These instruments are suitable to be mounted on the basic hydraulic bench by use of pipe union of easy and practical handling.
1. Flow circuit with 12 180째 degree radiused bends measuring 1355 mm in total length, to be connected to a differential pressure manometer to visualize the load losses due to any sharp change in the fluid flow direction.
2. Flow circuit as long as the proceeding one, featuring right angle bends, to be connected to a differential pressure manometer.
3. Flow circuit as long as the proceeding one, but with two 180째 degree radiused bends only, to be connected to a differential pressure manometer. Through these three instruments it is possible to measure the magnitude of the load losses occurring at the moderate and right angle bends and straight tubes, while the development in length of the flow circuits is kept as possible.
I - 16153 P.D. da Bissone 36r. GENOA - ITALY - Tel.: +39 010 6501969 Fax: +39 010 6501969 e-mail: patrone@ giacomopatrone.com http://www.giacomopatrone.com
3
GVF-1
4. Duct with a sharp widening and restriction in its crosssectional area to be connected to a differential pressure manometer.
5. Venturi meter designed to DIN Standard Specifications. Flow rate measurement totally coincident with that obtained through the rotameter.
6. Venturi meter with divergent wall arrangement (vein detachment). It is connected to water type differential pressure manometers for measuring the flow rate of water circulating the conduit. It has been designed with walls excessively divergent to visualize the vein detachment and the error of measurement into which one care incur when relevant DIN Standard Specification is not strictly adhered to.
7. Vacuum ejector (if connected to a mechanical manometer a vacuum condition higher than 90 percent can be obtained).
8. Nozzle. Constructive dimensions selected according to DIN Standard Specification. Practical results obtained are fully mating the theoretical ones. Measurements of flow rate perfectly coincident with that obtained by means of rotameter and Venturi meter.
9. Linear tube with specular-interior surface or rough conditions. This allows stressing out the qualitative and quantitative influence of roughness on the load losses.
10. The tube inclined 15째 with respect to the horizontal and 24/30 mm in diameter is directly connected to three water manometers in view of visualizing both piezometric and total loads. (Bernoulli theorem)
I - 16153 P.D. da Bissone 36r. GENOA - ITALY - Tel.: +39 010 6501969 Fax: +39 010 6501969 e-mail: patrone@ giacomopatrone.com http://www.giacomopatrone.com
4
GVF-1
11. VARIABLE TILTING FLUME – FLOW OVER A NOTCH with accessories for flow visualisation and flow measurements on different shaped weirs. The unit consists of a transparent variable tilt flume having a section of mm.150 x 150 and available standard length is mm.1400. An extension of mm.1000 length can be supplied upon request. Accessories included are three different shapes of plate weirs and two shapes of bottom weirs. The flume can be connected to the main water delivery line of the hydraulic bench by means of flexible tube and fast coupling and overflow is in an independent tank which drains directly in the bench collection tank so that mounting of the flume is easy and fast.
12. IMPACT OF A JET APPARATUS. This experimental unit consists of a Plexiglas cylinder inside which a water jet out of a nozzle is directed against different shaped models. The impact force can be evaluated by means of a spring balance. Models supplied are one hemisphere, one conical, and a model representing a pelton turbine palette. The water jet can also be oriented in order to evaluate effect upon the different angle of impact on the model under test. The unit can be connected to the basic hydraulic bench by means of fast couplings and flow is regulated by means of the speed variator of the feed centrifugal pump. Overflow is collected directly on the tray drip. Possible experiments are: ¾ investigation of the impact forces depending on the quantity and velocity of the water ¾ Influence of the impact on different shaped models. ¾ Influence of the impact forces depending of various impact angles
I - 16153 P.D. da Bissone 36r. GENOA - ITALY - Tel.: +39 010 6501969 Fax: +39 010 6501969 e-mail: patrone@ giacomopatrone.com http://www.giacomopatrone.com
5
GVF-1
CENTRIFUGAL PUMP INVESTIGATION With the basic hydraulic bench GVF/1 it is possible a complete educational investigation upon the principles of operation of a centrifugal pump. Using the included instrumentation, the following tests are possible: 他 detection of relevant delivery pressure 他 detection of relevant delivery flow 他 Plotting characteristic curves relevant to single stage centrifugal pump working at different speed. 他 Measuring of the electric power absorption under different operational conditions. In case of particular interest upon the study of the design of the different centrifugal pumps, a wide series of sectioned pumps and bladed rotors are available as a good complement for the comprehension of the working and design principles of the most common centrifugal pumps normally used in industry or civil applications.
SERIES OF 5 CENTRIFUGAL PUMP IMPELLERS
MULTISTAGE AND OPEN INPELLER CENTRIFUGAL PUMP
SELF PRIMING CENTRIFUGAL PUMPS (high lift type, open wheel type, with peripheral channels)
I - 16153 P.D. da Bissone 36r. GENOA - ITALY - Tel.: +39 010 6501969 Fax: +39 010 6501969 e-mail: patrone@ giacomopatrone.com http://www.giacomopatrone.com
6
GVF-1
POSSIBLE TESTS BY USE OF G.V.F. /1 ASSEMBLY In view of enabling students to get a knowledge and gain practical experience on a range of instruments of current use in water systems, a range of tests was developed by means of the "G.V.F. /1" assembly, making it possible for the students to become familiar with means currently used for measuring flow rate, pressure and friction losses in differential pressure manometers of water or mercury column type, metal valves, bypass regulating valves, etc. Students gain also practical experience on the correct use of mechanical differential pressure manometers and learn how to make various connections to instruments and providing relevant arrangement on the panel. The tests that can be performed with the visualisation means and experimental accessories are the following: 1. Flow rate measurement through nozzle and differential pressure manometer. 2. Flow rate measurement through Venturi meter of no-standard design. 3. Flow rate measurement through Venturi meter to DIN Standards and comparison of results obtained by this test to those of test N째.2. 4. Vacuum measurement obtained by means of water injector. 5. Measurement of friction losses due to a sharp widening of the cross-sectional area followed by a sharp reduction in the cross-sectional area. 6. Visualization of vortices through air bubbles, caused by the presence of a solid object (flange nozzle) inside the tube. 7. Visualization of vein detachment from the tube wall with excessive divergence. (Venturi meter of nostandard design). 8. Visualization of fluid flow caused by sharp changes in cross sectional area. 9. Measurement of friction losses due to gradual changes in flow direction. 10. Measurement of load losses due to friction in a tube with smooth wall surface and in a tube with rough wall surface condition. 11. Laminar and turbulent fluid flow visualization through air bubbles. 12. Measurement of piezometric load and relevant change in it caused by load losses. 13. Flow rate measurement by means of rotameter orifice and verification on it through a calibrated water tank that can be furnished on specific demand. 14. Flow visualisation at various tilt of the open channel, experiments with different shapes of weirs.
I - 16153 P.D. da Bissone 36r. GENOA - ITALY - Tel.: +39 010 6501969 Fax: +39 010 6501969 e-mail: patrone@ giacomopatrone.com http://www.giacomopatrone.com
7