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The use of passive, active, or hybrid flow control techniques is often investigated to reduce the acoustic signature, wave drag, and aerodynamic heating associated with the supersonic flow regime. This research explores passive and hybrid flow control techniques to achieve an optimal reduction in wave drag and aerodynamic heating on a blunt body using an aerodisk. While passive techniques use one or two aerospikes, hybrid techniques employ opposing jets and aerospikes. Numerical analysis is performed using Reynolds-Averaged Navier–Stokes (RANS) equations to analyze the bodies’ flow field. The statistical technique, Design of Experiments (DOE), is combined with Response Surface Method (RSM) to find the optimal configuration for four cases by generating design space. Two cases were considered for the optimization: single aerospike with and without opposing jet and double aerospike with and without opposing jet. Variables used for the design of the aerodisks were spike length and diameter, while the response variables were wave drag and normalized heat flux. The current study has established an optimum relationship between spike length and aerospike diameter located in front of the main blunt body for both single and double aerospikes. The study’s results suggest that a double aerodisk configuration is more beneficial for reducing drag and heat flux at supersonic speed than a single aerodisk. By incorporating an opposing jet at a pressure ratio of 0.8 from the frontal aerodisk to the spiked blunt body, it can reduce drag and heat flux by 86% and 95%, respectively. Finally, numerical verification is performed for statistically optimized designs.

The current numerical efforts were aimed at understanding the flow field around a blunt body and ultimately introducing a DOE process via the Response Surface Method (RSM). In addition, better application of passive and hybrid flow control techniques to alter the flow field was sought for aerodynamic drag and heat reduction. After numerical validation of the flow field with experimental cases, a response surface was created through the DOE process in which single and multiple aerodisks were introduced on a spiked blunt body, both with and without the inclusion of an opposing jet at a constant pressure ratio of 0.8. Two-dimensional steady-state simulations were performed by altering the frontal aerodisk diameter, length of the elongated aerospike, and the rear aerodisk over the total length of the spike. From the analysis, it was found that multiple-aerodisk spike configurations were advantageous for reducing wave drag and heating at supersonic speeds compared to a single aerodisk configuration. Mainly through the inclusion of an opposing jet at PR=0.8 from the frontal aerodisk on the spiked blunt body, reductions in drag and heat flux of approximately 86% and 95% were achieved, respectively. In summary, multiple-aerodisk spikes are highly efficient for reducing wave drag and heat by creating extra space for re-circulation zones in the elongated-spiked region. In addition, the use of an opposing jet further enhances drag- and heat-reduction efficiency. Moreover, numerical validation of statistical results generated via the RSM approach clearly indicated the effectiveness of the parametric optimization technique experimental design, demonstrating utility for future optimization studies.