The Analysis of Trajectory and Solar Aspect Angle Records of Shell Flights. Theory and Computer Programs

摘要

The theory and computer programs described in this report form part of a research programme in nonlinear dynamics. Methods and computer programs for obtaining aerodynamic coefficients from free flight trials of shells have been developed. The data from the trials consists of both trajectory data from either radar tracking of the shell or ballistic camera records of a flashing light carried in the shell, and complementary solar aspect angle measurements from yawsondes. The data analysis techniques will be used to investigate the exterior ballistics of shells. As well as a tool for investigating dynamic stability problems concering standard or modified shells they offer a new and more efficient approach to developing a Fire Control Model. An interesting facet of the data analysis is the representation of the aerodynamic force coefficients as analytic functions of Mach number, an approach which has potential for greater accuracy than the piecewise linear representation which is in general use. To facilitate use of the programs by the reader, program listings are supplemented by tables of input variables and sample output. Results from test runs using artificially generated data are discussed. (Author)