This article considers the problem of estimating dynamic derivatives of a basic finned projectile using computational fluid dynamic simulations. The indicial responses with respect to a unit step change in the effective angle of attack and pitch rate are calculated using a grid motion approach. The applications of these responses are then twofold: 1) they can be directly used to predict unsteady aerodynamic responses using a convolution integral; and 2) in addition, the indicial responses are used to calculate acceleration and rotary derivatives of the vehicle at different Mach numbers. These predictions are compared with available experimental data of the U.S. Army–Navy basic finner and those estimated from traditional oscillatory simulations. The results show that static and dynamic derivative numerical predictions match well with the experimental data over a wide range of Mach numbers. The outcome of this study is a demonstration of the ability of indicial response function methods to predict longitudinal dynamic derivatives, both for isolated input variables as well as combined values. The results reveal an ability to represent greater details of the flow features in the output derivatives compared to more traditional techniques. These benefits are in addition to the computational cost savings of using indicial methods to estimate dynamic derivatives rather than the use of traditional methods based on harmonic motions.
Indicial Methods for the Numerical Calculation of Dynamic Derivatives
AIAA journal ; 55 , 7
2017
Aufsatz (Zeitschrift)
Englisch
Indicial Methods for the Numerical Calculation of Dynamic Derivatives
Online Contents | 2017
|NTRS | 1961
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