Decay characteristics of an under expanded Mach 2 jet with perforated tabs

This experimental study examines the impact of supersonic C-D nozzle flows on improving the decay characteristics in supersonic and hypersonic aircraft, contributing to sustainable advancements in aerospace technology. A Mach 2 nozzle equipped with perforated angled tabs (0°, 5°, 10°, 15°, 20°, 25°, and 30°) was used in the present experiment to study the decay characteristics of the jet. It was anticipated that such a configuration would lead to improved mixing with the ambient flow and enhanced decay characteristics. To validate these expectations, pitot pressure experiments were conducted to examine jet decay and spreading characteristics. By comparing the performance of jets with and without the perforated tab, the findings revealed a significant reduction in the potential core length of the 30° controlled jet, which was 79.05% shorter than that of the baseline jet. The shock structures captured using the Schlieren technique confirmed the potential core decay. The vortical structures obtained from a brief computational study showed that the angled perforated jet demonstrated significant alterations in vortical structures near the nozzle compared with the baseline jet. These results underscore the efficiency of perforated tabs in enhancing jet decay, thereby offering promising avenues for the design of environmentally friendly supersonic combustor nozzles with improved overall performance.