Transient resonance of rolling finned projectiles

Citation
N. Ananthkrishnan et al., Transient resonance of rolling finned projectiles, P I MEC E G, 213(G2), 1999, pp. 97-103
Citations number
10
Categorie Soggetti
Aereospace Engineering
Journal title
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING
ISSN journal
09544100 → ACNP
Volume
213
Issue
G2
Year of publication
1999
Pages
97 - 103
Database
ISI
SICI code
0954-4100(1999)213:G2<97:TRORFP>2.0.ZU;2-K
Abstract
Finned projectiles that are intentionally spun are known to become locked i n at a resonance condition where the roil rate matches the pitch/yaw freque ncy. This phenomenon, called roll lock-in, results in an amplification of t he trim angle, which can lead to yaw instability. A less severe phenomenon is that of transient resonance where the roll rate locks in at resonance br iefly before continuing to build up to the design value. However, the trim amplification during the brief period of resonance may be sufficient to des tabilize the projectile. In this paper, the problem of transient resonance for finned projectiles with a centre-of-mass asymmetry is studied. Numerica l simulations are used to illustrate transient normal and reverse resonance . No yaw amplification is seen in both cases; rather the absolute value of the complex angle of attack shows a drop during passage through resonance. It is suggested that this is a general feature of the yaw response of finne d projectiles undergoing transient resonance.