Drag and Thermal Analysis of Hypersonic Aerospikes with Lateral Jets Using HiFUN

Hypersonic vehicles experience extreme aerodynamic heating due to intense shock interactions at speeds beyond Mach 5. Effective thermal management is critical to prevent structural damage and ensure mission success. Traditional mitigation techniques such as aerospikes and opposing jets offer partial improvements but introduce tradeoffs, including increased drag or flow instability. This study introduces a lateral jet configuration integrated with aerospikes as an innovative solution for reducing both thermal loads and aerodynamic drag. A comprehensive CFD analysis was conducted using the validated High-Resolution Flow Solver on Unstructured Meshes (HiFUN) under freestream Mach 5.75 and a static temperature of 140 K. Simulations were performed for three spike lengths (50, 75, and 100 mm) and three lateral jet pressures (2, 4, and 6 bar) to evaluate their influence on surface temperature and drag coefficient. A grid independence study was completed to ensure numerical reliability, and results were validated against established literature benchmarks. Findings reveal that lateral jet injection significantly reduces stagnation point temperatures—by up to 80%—and alters shock structures to enhance flow separation and recirculation. The 75 mm spike at 6 bar jet pressure was found to provide the most balanced performance, delivering optimal thermal shielding and minimal drag. Additionally, the use of lateral jets shifted the bow shock upstream, thereby reducing pressure on the nose cone but increasing localized drag on the aerodisk. This work demonstrates the viability of combining passive and active flow control strategies—optimized using HiFUN—for improved thermal management in hypersonic flight. The results can inform future aerospace designs requiring robust heat protection with aerodynamic efficiency.