Influence of Opposing Jet on an Aerodisk Nose Cone at Hypersonic Flow

Abstract

When flying at hypersonic speeds, it is a fundamental requirement to reduce the high drag resulting from a blunt nose cone in the ascent stage to increase the payload weight on the one hand and decrease the amount of energy needed to overcome the Earth’s gravity on the other. However, an aerospike can be attached on the front of the nose cone to obtain a high drag and heat load reduction. This study describes novel technique of an active flow control concepton nose cone with aerodisk that uses counterflowing jets to significantly modify external flowfields. In fact, this method strongly disperse the shock waves of supersonic and hypersonic vehicles to reduce aerothermal loads.Numerical simulations of a 2D axisymmetric aerodisked nose cone in hypersonic flow are conducted, and innovative techniques involving forward injection of gas from the stagnation point of the sphere are investigated; techniques include injection of various counterflowing jets (Helium and Carbon dioxide) as a coolant jet from the nose cone behind the aerodisk. In this study, the characteristics of the various jet conditions of a counterflowing jet on a cone surface were investigated numerically to improve performance of the jet on heat reduction at surface of a nose. Different Mach numbers at different altitudes have been chosen to investigate the effect of the aerospike on the nose cone’s surrounding flowfield. The drag and the heat load reduction is numerically evaluated at Mach numbers of 5.75. The results show that the lighter gas, Helium, is found to have a better cooling performance than Carbon Dioxide in low pressure ratios. The film cooling of Helium jet due to its lower specific heat capacity (Cp) character is efficient on heat load of the nose cone.

Investigation of thermal radiation on traditional Jeffery–Hamel flow to stretchable convergent/divergent channels

“…We should remark that in general conditions where asymmetry is also allowed, infinitely many solutions exist [38][39][40][41][42][43][44][45][46]. To keep the symmetry with regard to the centerline, we visit the same stretching/shrinking rates on both walls.…”

Forebody shock control devices for drag and aero-heating reduction: A comprehensive survey with a practical perspective

“…Spike root jet was examined by Gerdoorbary et al [321][322][323]. They claimed that root jet enhanced the aeroheating reduction capabilities of a spike.…”

“…By this augmentation, a jet can compensate short spikes while a spike can compensate low pressure jets [309]. Nonetheless, the benefits of the hybrid device diminish for longer spikes, higher jet pressures, and flow rate [307,321,328]. As for practical implementation of this hybrid device, the same concerns of the conventional opposing jet can be raised namely, space and power demands and source of jet.…”

Numerical study of shock wave interaction on transverse jets through multiport injector arrays in supersonic crossflow

“…The simulations were performed using an implicit CFD code [33][34][35][36][37][38][39]. This code solves NavierStokes equations using cell centered finite volume approach.…”