Accession Number : ADA134742

Title :   Inversion of Ringdown Data for a Rotating Liquid Cylinder.

Descriptive Note : Final rept.,

Corporate Author : ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD

Personal Author(s) : Aldridge,K D

PDF Url : ADA134742

Report Date : Sep 1983

Pagination or Media Count : 57

Abstract : Disturbance pressure data from both numerical and gyroscope experiments on ringdown of inertial waves were fitted to a sum of complex exponentials using a linearized least squares method. For the numerical experiments, frequencies and decay rates agreed with those predicted by eigenvalue calculations to within a few precent. Eigenfrequencies calculated from gyroscope data agreed with prediction to within 2% while all decay rates were greater than predicted, some by as much as 65%. An autoregressive method was developed and tested on both simulated and real data. At its present stage of development this approach was found to be inferior to the least squares method. (Author)

Descriptors :   *Numerical methods and procedures, *Mathematical models, *Least squares method, *Cylindrical bodies, *Eigenvalues, *Inversion, Computer programs, Pressure measurement, Computerized simulation, Tables(Data), Gyroscopes, FORTRAN, Experimental data

Subject Categories : Statistics and Probability
      Ammunition and Explosives

Distribution Statement : APPROVED FOR PUBLIC RELEASE