Dikey ve Paralel Yanaşma Yapıları Önünde Tekil Pervane Kaynaklı Oyulma Dinamiklerinin Deneysel Olarak Araştırılması

Abstract

Yanaşma ve ayrılma sırasında gemi pervanelerinin oluşturduğu jet akımları, yanaşma yapılarının stabilitesini ciddi şekilde tehdit edebilir. Giderek artan gemi boyutları ve kapasiteleriyle birlikte, pervane kaynaklı akımlar ile deniz tabanı erozyonu arasındaki etkileşimin anlaşılması, liman altyapısının korunması açısından kritik hale gelmiştir. Bu çalışma, çeşitli duvar konfigürasyonları altında tekil pervane jetlerinin oluşturduğu oyulma desenlerini deneysel olarak incelemektedir. Deneyler, ortalama tane çapı d₅₀ = 1,2 mm olan kum kullanılarak, 10 cm çapında pervaneler ve 4,71 ile 6,23 arasında değişen Froude sayılarıyla gerçekleştirilmiştir. Duvar bulunmayan (yapısız) ve duvar bulunan (dikey ve paralel) koşullar altında; pervane dönüş hızı, dikey boşluk (G) ve pervane-duvar mesafesinin oyulma üzerindeki etkileri analiz edilmiştir. Sonuçlar, yapısız durumda pervane ile yatak arasındaki mesafe arttıkça oyulma derinliğinin azaldığını; dönüş hızı arttıkça ise oyulmanın derinleştiğini göstermektedir. Yapılı koşullarda ise pervane-duvar mesafesi arttıkça oyulma derinliği azalmış, duvar yöneliminin de oyulma profili üzerinde önemli etkiler oluşturduğu belirlenmiştir. Elde edilen bulgular, rıhtım duvarları yakınında oluşan sediman taşınım mekanizmalarının anlaşılmasına katkı sağlayarak oyulma tahmin modellerinin geliştirilmesine olanak sunmaktadır.

Keywords

• Oyulma
• Erozyon
• Pervane jeti
• Rıhtım Duvvarı
• Yanaşma yapısı

Experimental Analysis of Single Propeller Scour Dynamics Near Vertical and Parallel Quay Walls

Abstract

Ship propeller jet-induced scour while berthing and unberthing poses a significant threat to berth structure stability. With the increase in size and capacity of vessels, the propeller-generated flow interaction with seabed erosion is gaining significance for port facility management. The present investigation experimentally investigates single propeller jet-induced scour behavior around quay walls of various wall configurations. Flume experiments in the laboratory were conducted with the use of sand of median grain diameter d₅₀ = 1.2 mm, 10 cm diameter propellers, and Froude numbers of 4.71 and 6.23. The role of rotational speed of the propeller, gap (G) vertically, and the propeller-wall distance were studied under conditions of unconfined (no-wall) and confined (parallel and vertical wall) cases. The results show that for unconfined cases, deeper gaps decrease scour depth and greater rotational speed increases it. In confined cases, deeper separation between the wall and the propeller decreases scour depth, and wall orientation significantly influences the scour profile. These kinds of results enhance understanding of the mechanisms of sediment transport near quay walls and allow for the development of predictive models for estimating scour.

Keywords

• Scour
• Erosion
• Propeller jet
• quay wall
• berthing structure

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