Contribution to Compressibility Modelling in the Estimation of Forces Acting on Projectile Fragments
Keywords:aerodynamic force, aerodynamic moment, compressibility, fragments
The compressibility model was developed and applied to generalized model for prediction of aerodynamic forces acting on irregularly shaped body, such as HE projectile fragments. Model assumes adiabatic compression of air in front of high‐velocity fragment since the motion of the fragment is an extremely fast process relative to the heat transfer process. The equation of the state of the ideal gas is adopted. Analysis of results and comparison with results obtained by numerical simulation (CFD software) and experimental data show this correction model significantly reduces the relative error of aerodynamic force modelling in the relevant area of the high velocity of the fragment, when the air compression is significant.
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