The present study focuses on experimental techniques to understand the self-excited oscillation characteristics in low-density round for fully developed and turbulent flow conditions, as well as rectangular jets, and study the effects Reynolds number, momentum thickness, density ratio and aspect ratio on self-excited oscillation. Two global modes exist in low-density round jets. The results confirms that oscillations in low-density round jets are axisymmetric irrespective of S and D/θ, and turbulent jets can exhibit self-excited oscillations for S ≤ 0.53.

Protostellar jets are fossil records of the accretion history of protostars. Studying these jets opens up an indirect window of knowledge into the evolutionary stages and activities of the protostar, the direct study of which is difficult due to its highly embedded nature. The research highlights a theoretical and observational study of protostellar jets in radio and near-infrared wavelengths, respectively.

N-Dodecane plays a crucial role in surrogate fuels for gasoline and jet fuels. Selecting the right surrogate fuel combination depends on the properties of its individual components. Precise reaction mechanisms are essential to predicting combustion characteristics, including laminar burning velocity and ignition delay times. Unfortunately, data for n-dodecane-air, oxy-n-dodecane with diluents like N2, CO2, H2O, and n-dodecane-H2-air are scarce in the literature. This study aims to bridge this gap.

Black hole X-ray binaries (BH-XRBs) are gravitationally bound associations of a com

Transitional flows with an unsteady inflow play a vital role in a broad range of applications, including biological fluid transport to space applications. In such cases, the thickness of the boundary layer formed over the solid surface varies in both space and time, causing a high level of complexity in the path of vortical structures formed from the shear/boundary layer. Also, time and space-dependent shear stress exerted by the fluid, separation, and associated instability phenomena are to be better understood.

Due to the increased use of cube- and nano-satellites, the demand for micro-propuls

 Nacre, bone, spider silk, and antlers are some examples of biological composites that exhibit a great combination of mechanical properties such as high strength, stiffness, and toughness when compared to that of their constituents using which they are made up of. This has inspired many researchers to investigate bio-inspired composites to explore the possibilities of making synthetic composites with superior mechanical properties using relatively weaker constituents.

First phase of the research work focuses on dynamic modeling and ascent flight control of a highly unstable and flexible launch vehicle. Stabilizing adaptive PD/PID controllers are developed in MRAC framework using standard quadratic Lyapunov function to control the time varying rigid body dynamics during the atmospheric phase of flight. Further, Lyapunov stability and Barbalat’s Lemma are applied to prove the stability of the time-varying system.

Electrochemistry deals with the relation between electrical and chemical phenomena and has an ever-increasing impact on everybody's daily life. Out of the myriad applications of electrochemistry, considerable attention has been devoted to the fields of electrochemical (EC) sensing in recent decades because of its inherently fast, accurate, compact, portable, and cost-effective properties.

This dissertation is explored the photonics inter sub band transitions (ISBT) phenomenon in an electronics Gallium Nitride (GaN) high electron mobility transistor (HEMT) device. Conventional photonic devices are operated at cryogenic temperatures to minimize the thermal effect. The reported maximum operating temperature of THz quantum cascade laser (QCL) is in the range of 150-200 K which is too low for general applications. The conduction band tuning through external gate bias makes advantage of HEMT device for room temperature (RT) terahertz applications.