On the Reductions of Aerodynamic Drag and Heating of a Blunted Cone

The present study numerically investigates the effect of Mach 5.8 flow past different stepped taper spikes on the aerodynamic drag and heating of a blunted nose cone. The effect of different spike taper angles (2.5°, 5°, 6.25°, 7.5° and 10°) and step depths (0.15, 0.2, 0.25, 0.5 and 1.0 mm) provided at the root of the spike, on the drag and heating of a blunted cone are compared with a straight one having the same spike length and step width to ascertain the best taper spike which provides the lowest drag coefficient and heat flux. The heat flux decreases with the increase of spike taper from 0 to 7.5°, while it remains almost constant beyond 7.5° taper. Further, the decrease in the drag coefficient is almost negligible beyond a spike taper of 7.5°. It shows that the best spike taper for minimum drag and heat flux is 7.5°. The effect of step depths on a 7.5° spike taper reveals that the best spike depth for minimum drag and heat flux is 0.15 mm. Mach contours show shock structures such as leading shock, separation shock, and re-attachment shock, while the velocity vectors show flow features around the spike/nose.