Supercavity Enhancement in High-Speed Heavyweight Torpedoes: Exploring the Role of Secondary Cavitator

Abstract

Underwater warfare in the modern world demands the development of fast, supercavitating torpedoes. Torpedoes typically achieve supercavitation via a single cavitator mounted at the nose; the cavitator’s dimensions dictate the supercavity size. This study introduces a novel approach of incorporating a secondary cavitator to enhance the supercavity and improve the performance of supercavitating torpedoes. Numerical simulations are performed using Reynolds-averaged Navier – Stokes equations solved with a pressure-based algorithm. The volume of fluid (VOF) multiphase model, in conjunction with the Schnerr–Sauer cavitation model, is employed to model the supercavitation phenomenon. The effects of cavitator size, positioning, and operating conditions on supercavity behavior are also examined. Results indicate that positioning the secondary cavitator at 70%–90% of the primary supercavity length significantly enlarges the supercavity, achieving a 30%–35% increase in supercavity length. The optimal size for the secondary cavitator is also identified, beyond which reverse flow and cavity shrinkage occur. The dependence of the secondary cavitator’s critical size on the primary cavitator’s diameter and Froude number is further investigated. This research provides new insights into the design of supercavitating vehicles and establishes a framework for optimizing cavitator configurations in heavyweight torpedoes.

Keywords

Supercavitation / High-speed torpedo / Multiphase flow / Cavitator / Cavity enlargement / Underwater vehicles

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