The Water Resources Engineering (WRE) laboratory at IIT Gandhinagar has several facilities to conduct teaching and research activities.
Experimental set-ups for Teaching Courses
This apparatus consists of a glass tube with one end having bell mouth entrance connected to a constant head water tank and at the other end a valve is provided to vary the flow rate. The tank has sufficient capacity to store water for conducting the test. A capillary tube is introduced centrally in the bell mouth for feeding dye from a small container placed at the top of tank, through polythene tubing. By varying the rate of flow, the Reynold’s number is changed. This also changes the type of flow (turbulent, laminar and transition). Visual observation of dye will indicate the type of flow, which can be confirmed from the Reynold’s number computation. Present setup is a self-contained water recirculating unit, provided with a sump tank and a centrifugal pump. Flow control valves and bypass valves are fitted in the water line. Flow rate of water is measured with the help of measuring cylinder and stopwatch.
A Pitot tube is used to measure the local velocity at a given point in the flow field. A Pitot tube of standard design made of copper/SS is supplied and is fixed below the Vernier scale, which is capable of measuring the position of the Pitot tube in a transparent pipe section. The pipe has a flow control valve to regulate the flow. A U-tube manometer is provided to determine the velocity head. Present Set-up is a self-contained water recirculating unit, provided with a sump tank and a centrifugal pump. Flow control valves and by-pass valves are fitted in the water line to conduct the experiment on different flow rates. Flow rate of water is measured with the help of a measuring tank and stopwatch.
Apparatus to verify Bernoulli Equation
Bernoulli Equation is based on conservation of energy and is applied to study fluid flows. It has many real-world applications, ranging from understanding the aerodynamics of an airplane; calculating wind load on buildings; designing water supply and sewer networks; measuring flow using devices such as weirs, Parshall flumes, and venturi meters; and estimating seepage through soil, etc. This set up is used to measure different components of the energy head for a steady flow of water through a tapered duct and to investigate the validity of the Bernoulli equation.
Free and Forced Vortex Tube Setup
The Free and Forced Vortex Tube Apparatus consists of a cylinder provided with a drain at the center of the bottom. The cylinder is fixed over a platform which can be rotated at different speeds with the help of a D.C. motor. A tangential water supply rip is provided with a flow control valve. The whole unit is mounted over the Pump tank. Water is supplied by a centrifugal pump.
The pressurized vortex tube can be used to determine the extent to which the produced streamwise vorticity could be maintained downstream. It is used to understand the flow behaviour inside a vortex tube. It can also be used to develop and test an acceptable hypothesis for the energy separation in a vortex tube.
Impact of Jet Apparatus
The Impact of a Jet apparatus is used to know the force produced by a jet of water as it strikes a flat plate or hemispherical cup. Then the comparison of this force to the momentum of the flow rate in the jet is performed. Thus, the momentum equation for a fluid flow can be verified.
Impact of Jet Vanes
The objective of this setup is to investigate the reaction forces produced by the change in momentum of a fluid flow when a jet of water strikes a flat plate or a curved surface, and to compare the results from this experiment with the computed forces by applying the momentum equation.
Venturi meter and Orifice meter
The Venturi meter and Orifice meter Apparatus is designed for calibration of water flow meters. The Set up consists of a venturi meter and orifice meter fitted in a pipe. Each flow meter has two pressure ports which can be connected to a mercury manometer to measure pressure difference at inlet and throat. This pressure difference is used to calculate the water flow rate by using the Bernoulli Equation. Water is supplied from the sump tank by centrifugal pump and measuring tank is provides the water flow rate. The entire setup is mounted on a strong steel frame. By comparing the theoretical and measured flow rate, the discharge coefficient for flow meter can be determined.
Flow through Nozzle meter
It is used for determining the coefficient of discharge at different flow rates.
Basic Hydrology Apparatus
It is a self-contained floor standing unit consisting of a water reservoir and a tank with sand. Overhead spray nozzles simulate rainfall. It is for studying different principles of hydrology including rainfall, throughflow and the movement of water over land and rivers.
Experimental set-ups for Research
The WRE laboratory has three different flumes:
- The first flume is a long tilted flue. Its discharge and tilt can be set through a control panel. The main channel dimensions of the flume are 12.3*0.55*0.6 in metres. It has several accessories such as mats with different roughnesses, bridge piers, wave maker) to support several hydraulic studies for rigid bed and mobile bed open channels.
- The functioning of the second flume is manual, i.e., the discharge and the tilt are set manually. The dimensions of the flume are 3*0.22*0.38 in metres.
- The third flume is for studying combining junction flows. It has two inlet channels (at right angle to each other) and one outlet channel. The dimensions of the main channel in metres are 5*0.5*0.75 and lateral channel dimensions are 2*0.5*0.75. This flume can support both rigid bed and mobile bed flows.
Levee Breach Setup
Levees and flood walls are constructed along the rivers to protect cities and other residential areas which are under flooding risk. However, these protective structures may fail during high floods and cause fatalities and extensive property loss. The levee set up in the WRE laboratory contains two water tanks having upstream and downstream tanks. A pump and motor unit is installed to pump water from the downstream water tank to the upstream water tank. At the u/s water tank, a sluice gate is installed to control the discharge. Steel plates with zigzag pattern are placed before the sluice gate to reduce the water velocity and control flow regime. The d/s sluice gate is provided to maintain the flow depth. The erodible levee structure is made at a certain location to investigate its breaching phenomena. The measurements from the set-up may also be used to validate numerical models.
Detecting partial blockage in a piping system
The piping system is connected to a pneumatic tank on the upstream end and to a valve at the downstream end. Partial blockages in the form of orifices can be fitted to the piping system. Pressure transducers are fitted at several places. The transient is created by suddenly closing the valve. Different signals of the transient is recorded by varying the location, size and number of the partial blockages. The signals are studied inversely to detect the blockages.
High Speed Video Camera
This camera captures a single image on a frame of video and then advances to the next frame. The framing rate (fps – frames per second) determines how many opportunities the user has to view the event during the event cycle. Playing this sequence of frames, offers a “super slow motion” video experience. The shutter speed is independently set and determines the “stop motion” capability of the camera. The faster the shutter, the less blur will be seen in the individual images (frames).
3D Velocity measurement device (VectrinoPlus)
This is a acoustic based device. The vectrino plus is used to collect the three-dimensional velocity data. The working principle of the equipment is based on the Doppler effect. The 3D velocity data are measured using 10-MHz downward-looking probe. The signal-to-noise ratio (SNR) and correlation values are set to the thresholds of > 20db and > 70 percent, respectively.
It is a video game device which is a line of motion sensing input device made by Microsoft. Kinect has an RGB camera, infrared projector and detector which can map depth through the time of flight calculations and a microphone array. Kinect can be used successfully to map the underwater objects.
Bed-load Measurement Device
Pipe Fiber Bragg Grating system:
This system has been developed in the WRE laboratory. It is used to measure the flow rate, and the particle grain size distribution of the flowing bed load sediment. The device is capable of detecting particles as small as 8 mm in flume settings.
Impact plate Geophone system:
This system (assembled in the WRE laboratory) is used to study the interaction of bedload particles with the impact plate in the flume conditions. The device is capable of estimating bed load discharge and particle grain size distribution with particles greater than 16 mm.