Finding optimal hull shapes for fast vertical penetration into water

TL;DR

This paper introduces a combined CFD and analytical method to optimize supercavitating hull shapes for high-speed water penetration, demonstrating that slender cavitators improve depth and reduce loads.

Contribution

It presents a novel integrated approach for hull shape optimization using CFD and analytical methods, specifically for supercavitating vehicles at 1 km/s speed.

Findings

Slender cavitators reduce local pressures and improve penetration depth.

Optimized conical hulls outperform initial cylindrical designs.

Cylindrical hulls with slender cavitators achieve deep penetration with low loads.

Abstract

A new approach for the supercavitating hull optimization was proposed, which combines the CFD simulation and analytical methods. The high-speed penetration into water at the velocity 1 km/s was considered with the fixed body mass and caliber. Six different axisymmetric hulls with disc, 30{\deg} and 10{\deg} conical cavitators were simulated with the use of FLUENT at the first stage of penetration (till the 6 m depth). The optimized hull shapes were calculated with the use of quasi-steady approach and the characteristics obtained by CFD simulation. The use of slender cavitators drastically decreases the local pressures, but the higher friction drag also reduces the depth of supercavitating penetration. Optimized conical hulls can ensure much deeper penetration in comparison with the initial cylindrical hulls. The slenderest cavitator with the cylindrical hull ensures small loads and very deep penetration.