Flow Control & Turbine Research Lab (Flow-CTRL)

Flow Control & Turbine Research Lab

Lab Profile

The Lab has been set up with a vision to study the flow behavior in different scenarios (practical & fundamental aspects) and effectively find ways to control the flow field. Flow controls (active and passive) are investigated to enhance the desired output from the study. The research group focuses on flow control for both macro and micro scales. The flow field analysis is performed over the bluff bodies and aerodynamically designed biomimetic objects and turbine blades. Experiments are performed using a Wind tunnel to enhance their drag reduction and heat transfer enhancement Equipment.

Dr. Sushanta Dutta is an Associate Professor of Indian Institute of Technology, Roorkee. His research interest includes experimental fluid mechanics and heat transfer. He has work experience in the field of Optical Measurement Techniques, Active and Passive Control of Flow Wake Dynamic and Turbulence. Fluid mechanics in biomimics and microfluidics has also been included in his broad area of expertise

Area Of Research
• Flow control and visualization
• Jet flow and Synthetic jet
• Bluff body Aerodynamics
• Aerofoil and Turbine baldes
• Microfluidics: Fabrication and analysis
• Heat tranfer augmentation
• Drag reduction
• Flow transition and instability
• Micro Aerial Vehicles

Equipments

1) Wind Tunnels

The lab has 3 wind tunnels two for flow analysis and one for heat transfer study. Above figures show a big tunnel with test section- 0.61m X 0.61m and 2.72m in length. Maximum speed that can be achieved is 15 m/s. Test section has transparent acrylic sheet walls on 3 sides (top and adjacent to the top) up to the length of 1.52m. Hence can be used for flow visualisation using smoke generator or can be used for PIV measurements. Effect of flow over Aerofoil, MAVs and bluff bodies are currently been done using it. The dimension of test-section of smallest tunnel is 10cm X 15 cm.

2) Particle Image Velocimetry (PIV) System

The two dimensional PIV consists of a dual pulsed laser (200 mJ) system, a synchronizer, high resolution CCD camera (2048 x 2048 pixels), a high speed workstation and a three axes traverse. The laser straddle at 15 Hz frequency. The setup measures the U and V component of velocity and their gradients in a flow field without any intrusion of probe. The other derivatives of the flow field like vorticity, Reynolds stress and turbulence intensity can also be obtained using PIV setup. The pulse separation time between two frames ‘Δt’ is kept = 100 μs and 500 realisations have been taken to obtain time-averaged flow field. Recursive Nyquist criteria has been used for cross-correlation between two frames of images with minimum interrogation window size of 24 x 24 pixels and overlap of 50 % is applied.

3) Hotwire Anemometer (CTA) and Pressure Transducers

Hotwire Annemometer used is constant temperature type. CTA is particularly suitable for measurement of flows with fast fluctuation. It is capable of measuring minimum flow speed of 0.1 m/s and its uncertainty is in the range of 2%. Maximum sampling frequency is 125KHz. It can measure 2D velocities simultaneously. It is beneficial as it provides instantaneous velocity at a continuous analog outputwith very high temporal resolution. It is accompanied with a traverse system capable of giving very high resolution in all 3 direction of movement. CTA equipment is capable of using more than one probe which enable high precission for highly turbulent flow. The frame is computer controlled and can house upto 6 channels.The velocity measurements can be performed with high spatial and temporal resolution, high dynamic range and good accuracy.

4) Schlieren System

Schlieren photography is a visual process that is used to take pictures of flow field having variable densities. It has application wherever the flow density changes because of eother the temperature difference as in case of fire or due to velocity(Pressure) as in case of compressible flows. The system uses a 75mW HeNe Laser source to illuminate the field of view and array of lense arrangement is used to get the desired image using a CCD camera.

5) Liquid crystal thermography LCT

6) Flapping wing Active control

The work is done using Load cell/ Force Transducer and High-Speed Camera. The average field is analysed using PIV. Piezo actuator is used to control the flow over a flapping aerofoil and FWMAV

Projects

Major Research Projects

Numerical & Experimental Studies on Solar Air Heater with Surface Mounted Obstacles

Characterisation of wake and suppression of fluid forces acting on a row of square prisms

Study of flow field over a square prism for vortex load reduction using active and passive contro

Flow control and heat transfer enhancement over a surafce mounted obstcale using synthetic jet

Experimental investigation of unsteady aerodynamics and flow control for flexible structure

Experimental and Numerical Study of Bio-inspired Micro-textured surface for Drag Reduction

The unsteady Aerodynamic response in LP turbine blade and its control under part load conditions

Development of micro-fluidic system for Bio-Medical Application