Academics

Bachelor’s Thesis Title | Design an intermittent supersonic blow-down wind tunnel
Advisors: Prof. V. Ramjee and Prof. E. Rajakuperan
An intermittent supersonic blow-down wind tunnel of test-section size 100 mm by 25 mm is designed to simulate a freestream Mach number of 2.0 for about 30 seconds. The design includes the sizing and selection of commercially available compressors, air storage tanks, filters, and valves. Emphasis is given on the contoured nozzle design using a minimum-length convergent-divergent nozzle through the method of characteristics. A detailed calculation involving the estimation of an operational envelope of the blow-down facility through iterative methods is also performed. The designed blow-down facility’s flow uniformity and conditions are later verified through a commercial fluid flow solver. 

Master’s Thesis Title |  Aerodynamics of a projectile in ground proximity at supersonic speed
Advisors: Prof. J. K. Prasad and Prof. Sudip Das
In the present study, a model of NATO 5.56 mm ammunition is selected. Series of experiments and computations are performed to obtain the aerodynamic coefficients. Supersonic Wind Tunnel has been used for Schlieren/Shadowgraph flow visualization, oil flow visualization, static pressure measurements, and forces and moment measurements using a 3-component strain gauge balance. Experiments are conducted at various ground heights for a few angles of attack. Computations are made using ‘fluent’ and adopting the S-A turbulence model. At different Mach numbers, the computed results are in good agreement with experimental results. The obtained aerodynamic coefficients are further utilized to estimate the trajectory.

Doctoral Thesis Title | Experimental studies on mixing in a supersonic confined jet
Advisors: Prof. K. P. J. Reddy and Prof. G. Jagadeesh
An existing rectangular supersonic ejector is used to study the aspects of mixing encountered in a supersonic confined jet. Air is used as the working fluid in both the primary and secondary flow. The primary flow is supersonic and the secondary flow is subsonic. Effects of the primary flow Mach number and the secondary flow rate on the gaseous mixing in the confined jet are studied. Non-mixed length, mixed length, and potential core length of the primary flow are used as key parameters in the mixing studies. Mie scattering (PLMS), laser-induced fluorescence (PLIF), and particle image velocimetry (PIV) are used as flow diagnostics. Linearity in the mixing progression, lengthening of the potential core, the encountering of a multitude of unstable modes are a few of the key findings in this work.