INVESTIGATION OF THE EFFECT OF THE FLOW REGULATORS ON THE FLOW AROUND A GENERIC SUBMARINE SAIL

Year 2022, Volume: 18 Issue: 2, 251 - 279, 30.11.2022

Gökay Sevgi , Barış Barlas , Oral Ünal

Abstract

In this study, the viscous flow field around the mainsail of the DARPA Suboff AFF8 generic submarine fitted with two flow regulators in tandem configuration was investigated by means of computational fluid dynamics. An effective solution for the improvement of the mainsails of some of the current submarine classes of the Turkish Navy was aimed by covering the prepositioned periscopes by the flow regulators to avoid drag and vorticity increases due to the complex flow structure generated by these appendages and to provide a smoother flow topology. Three different NACA profiles with the same chord and span lengths were specified for regulating the flow. The effect of the NACA profile geometries on the hydrodynamic resistance and the flow field characteristics around the sail was demonstrated. It was shown that different profiles selected for the flow regulators considerably affect the computed resistance, velocity, pressure and vorticity characteristics of the flow field around the flow regulators. However, the flow structure at the side zones of the mainsail was not affected by the flow regulators. The profiles selected from NACA 6-digit and NACA 16-digit series give better hydrodynamic performance than their classical NACA 4-digit equivalent.

Keywords

Submarine, Tandem Hydrofoils, Computational Fluid Dynamics, RANS

Thanks

The authors would like to thank STM Inc. for the valuable discussions related to the topic.

AKIŞ DÜZENLEYİCİLERİN BİR JENERİK DENİZALTI YELKENİ ETRAFINDAKİ AKIŞA ETKİSİNİN İNCELENMESİ

Abstract

Bu çalışmada, üzerine tandem konfigürasyonda iki akış düzenleyicinin konumlandırıldığı jenerik DARPA Suboff AFF8 denizaltısının yelkeni etrafında gelişen viskoz akım alanı hesaplamalı akışkanlar dinamiği ile incelenmiştir. Türk Donanması’nın mevcut denizaltı sınıflarından bazılarının ana yelkenlerinin iyileştirilmesi için periskopların oluşturduğu karmaşık akış yapısından kaynaklanan direnç ve girdaplılık artışlarını önlemek ve daha düzgün bir akış topolojisi sağlamak maksadıyla, önceden konumlandırılmış bu takıntılar akış düzenleyiciler ile çevrelenerek efektif bir çözüm hedeflenmiştir. Akışı düzenlemek için aynı kiriş ve açıklık boyuna sahip üç farklı NACA profili belirlenmiş ve bu NACA profili geometrilerinin hidrodinamik dirence ve yelken etrafındaki akım alanı karakteristiğine etkisi gösterilmiştir. Akış düzenleyiciler için seçilen farklı profillerin, akış düzenleyicilerin etrafındaki akım alanı için hesaplanan direnç, hız, basınç ve girdaplılık karakteristiklerini önemli ölçüde etkilediği görülürken ana yelkenin yan bölgelerindeki akım yapısını etkilemediği gözlemlenmiştir. NACA 6 ve NACA 16 serilerinden seçilen profiller, klasik NACA 4 serisi eşdeğerlerinden daha iyi bir hidrodinamik performans vermektedir.

Keywords

Denizaltı, Tandem Hidrofoiller, Hesaplamalı Akışkanlar Dinamiği, RANS

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