The aim of this project is to study the effect of flow inside the subsonic co-axial nozzle used in aircraft turbofan engine. The study has been carried out by varying the Mach number of secondary flow by maintaining the constant Mach number of primary flow. The coaxial nozzle of the circular section was designed and analysed using CATIA and ANSYS V15.0 software for a Mach number range of 0.3 to 0.6 with secondary sub-sonic flow .The pressure and velocity contours were investigated along the flow. The increase in the velocity difference between the primary and secondary flow results in more turbulence which in turn decreases the potential core length.

Recent trends in aircraft design research have resulted in development of many unconventional configurations mostly aimed at improving aerodynamic efficiency. The blended wing body (BWB) is one such configuration that holds potential in this regard. In its current form the BWB although promises a better lift to drag (L/D) ratio it is still not able to function to its maximum capability due to design modifications such as twist and reflexed airfoils to overcome stability problems in the absence of a tail. This work aims to maximize the impact of a BWB. A design approach of morphing the BWB with a conventional aft fuselage is proposed. Such a configuration intends to impart full freedom to the main wing and the blended forward fuselage to contribute in lift