INERTIAL- AND FLOW-INDUCED ACOUSTIC MODES COUPLING IN UNSTEADY-ROTATING CYLINDRICAL FLUID-FILLED CAVITIES

✍ Scribed by D. ECOTIERE; M. BRUNEAU; N. TAHANI

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 311 KB
• Volume: 252
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.2001.4025

✦ Synopsis

A previous investigation has used a procedure for analyzing the transient behaviour of acoustic gyrometers, providing advances in &&inertial}acoustic'' theory and modelling. The approximate behaviour of the Coriolis acoustic modes coupling in a gyroscopic #uid-"lled cylindrical cavity, for a very fast variation of the rotation rate of the cavity, has been derived, showing, after the stabilization of the rotation rate of the #uid, an asymptotic value of the sensitivity in good agreement with the theoretical steady state value and with the experimental result for steady rotation. However, the parameters which govern the transient response, its shape and its characteristic stabilization time, were not fully identi"ed. Especially, the analysis does not predict recent experimental results, which show a stabilization time for the transient response of the gyro much shorter than the stabilization of the unsteady circular #ow created when the walls of the cavity are set impulsively (Heaviside step function) in rotation. Thus, it is the aim of the present paper to investigate more deeply, analytically, the transient behaviour of the acoustic gyro, using a revisited description for the inertial}acoustic modes coupling which conveys signi"cant improvements and introducing new features (as the #ow-induced acoustic modes coupling) neglected in the previous investigation. The theoretical results are in good agreement with the experimental results now available; they also permit both to interpret the physical phenomena which underlie the &&inertial}acoustic'' transient process and to address requirements that have to be taken into account in the design of acoustic gyros.

2002 Elsevier Science Ltd.