Design of Optimized Two-Dimensional Scramjet Nozzle Contour for Hypersonic Vehicle Using Evolutionary Algorithms

Abstract

The supersonic combustion ramjet (scramjet) engine proposed by F. S. Billig in 1964 has been perceived as the most hopeful air-breathing propulsion system for the hypersonic flight. The nozzle plays a vital role in accelerating heated air from the combustor to produce thrust in a scramjet engine. In the present study, a design methodology has been established using an in-house developed Python scripts for the automation process of computational fluid dynamics (CFD), artificial neural network (ANN), and optimization due to the nonlinear nature of the problem. The nozzle geometry used in this method consists of the inner surface which is represented by a cubic curve. The optimization is carried out for a hypersonic cruise vehicle nozzle designed to fly at Mach number of 6 and an altitude of 30 km with single expansion ramp nozzle as the baseline geometry. The results show that the optimized nozzle contour generates 16.7 % more thrust when compared to the baseline geometry for similar flow conditions.