Optimal Design Of Superdetonative Ram Accelerators For Hypersonic Velocities

Author :
Publisher :
ISBN 13 :
Total Pages : 63 pages
Book Rating : 4.:/5 (227 download)

DOWNLOAD NOW!

Download or read book Investigation of Superdetonative Ram Accelerator Drive Modes written by and published by . This book was released on 1989 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents the results of experimental and theoretical investigations of high velocity modes of the ram accelerator, a ramjet-in-tube projectile accelerator whose principle of operation is similar to that of a supersonic airbreathing ramjet. The projectile resembles the centerbody of a ramjet and travels through a stationary tube filled with a premixed gaseous fuel and oxidizer mixture. The tube acts as the outer cowling of the ramjet, and the combustion process travels with the projectile, generating a pressure field which produces forward thrust on the projectile. Different modes of combustion have been explored for accelerating projectiles of nearly identical geometry. Subsonic, thermally choked combustion theoretically allows a projectile to be accelerated to the Chapman-Jouguet (C-J) detonation speed of a particular gas mixture. In the superdetonative regime the same projectile is accelerated while always traveling faster than the detonation speed, and in the transdetonative regime (85-115% of detonation speed) the same projectile may transmit smoothly from a subsonic to a supersonic to a superdetonative combustion model. This report examines operation in these three regimes of flow up to velocities approaching 2500 m/s in a 12.2 m long, 38 mm bore ram accelerator, using projectiles of 45-75 gm mass.