Novel Design Proposal of an Elliptical Cross-Section Dual-Bell Nozzle with Comparative Analysis to Conventional Dual-Bell Nozzle

The continuous advancement of space exploration has led to increasing demand for high-performance propulsion systems, which are critical for mission success, cost efficiency, and payload maximization. To address these requirements, innovative nozzle configurations are being explored to improve the propulsion efficiency and enhance the payload capabilities. Among these, the dual-bell nozzle stands out as a promising concept due to its dual-mode operation, enabling efficient performance under both sea-level and high-altitude conditions. Likewise, elliptical nozzles offer distinct advantages such as improved thrust vectoring, more uniform exhaust flow distribution, and reduced structural mass. In this study, a novel rocket nozzle configuration is introduced. This configuration represents an elliptical dual-bell nozzle, which integrates the dual-bell concept with an elliptic cross-section geometry. A numerical investigation employing computational fluid dynamics (CFD) is carried out to estimate the thermodynamic performance of the proposed design. A comparative analysis with a conventional axisymmetric dual-bell nozzle is also given. The results show that the elliptical dual-bell nozzle achieves a 28.93% increase in both the generated thrust and the thrust coefficient, thereby demonstrating the significant performance potential of the proposed design.