Alekseevskii-Tate revisited: An extension to the modified hydrodynamic theory of long rod penetration

The modified hydrodynamic theory of long rod penetration into semi-infinite targets was established independently by Alekseevskii and Tate over forty years ago and since then many investigators contributed much to the development of the high speed penetration mechanics. However, in all the models proposed so far, the target resistance Rt is not well defined and usually determined by adjusting it until the predicted depth of penetration comes to an agreement with experimental data. In this paper, assumptions are first made about particle velocity and pressure profiles together with response regions in the target and then an extension is made to the modified hydrodynamic theory of long rod penetration into semi-infinite targets, in which Rt has explicit form and is dependent on penetration velocity as well as thermo-mechanical properties of target material. The present model is compared with long rod penetration tests for different material combinations. It transpires that the present model predictions are in good agreement with the experimental data and numerical simulations in terms of penetration depth although many assumptions and simplifications are introduced into the paper.