Contribution to Compressibility Modelling in the Estimation of Forces Acting on Projectile Fragments

Elvedin Kljuno; Alan Catovic

doi:10.3849/aimt.01371

Authors

Elvedin Kljuno Mechanical Engineering Faculty, University of Sarajevo, Bosnia and Herzegovina
Alan Catovic Mechanical Engineering Faculty, University of Sarajevo, Bosnia and Herzegovina

DOI:

https://doi.org/10.3849/aimt.01371

Keywords:

aerodynamic force, aerodynamic moment, compressibility, fragments

Abstract

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.

Author Biographies

Elvedin Kljuno, Mechanical Engineering Faculty, University of Sarajevo, Bosnia and Herzegovina

University of Sarajevo

Mechanical Engineering Faculty

Defense Technology Department
Alan Catovic, Mechanical Engineering Faculty, University of Sarajevo, Bosnia and Herzegovina

University of Sarajevo

Mechanical Engineering Faculty

Defense Technology Department

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