Investigation of clasical and bottom-inlet spillway aerator performances by numerical model

Year 2022, Volume: 11 Issue: 1, 148 - 156, 14.01.2022

Mehmet Cihan Aydın , Muhammed Reşid Özdemir

https://doi.org/10.28948/ngumuh.873077

Abstract

The spillways, which are the most important hydraulic elements of the dams, are designed in many different types according to the dam type and flow rates. One of the most important issues to be considered when designing spillways is the design of the aerators. In this study, the cavitational damage on the concrete surface of spillways and the effects of aerators on the cavitation wer investigated. For this purpose, a three-dimensional numerical model of a selected spillway model was prepared and Computational Fluid Dynamics (CFD) analyzes were performed in different Froude numbers. Later, a different type of aerator called as the bottom-inlet aerator was placed in the model and CFD analyzes were performed similar to the original aerators. The results obtained from the CFD analysis were compared with each other and it was concluded that both aerators were sufficiently protected from cavitation damage. The results obtained were also compared with the aerator results obtained with different types and methods in the literature.

Keywords

Spillway, Flow 3D, Aerator, Cavitation, Numerical analysis, CFD

Klasik ve alttan alışlı dolusavak havalandırıcı performanslarının sayısal modelle incelenmesi

Abstract

Barajların hidrolik açıdan en önemli elamanı olan dolusavaklar baraj tipine ve geçireceği debilere göre birçok farklı tipte tasarlanmaktadır. Dolusavaklar tasarlanırken dikkat edilmesi gereken en önemli hususlardan biri de kavitasyon önleyici havalandırıcılardır. Bu çalışmada dolusavaklarda beton yüzeyinde oluşan kavitasyon hasarı ve dolusavak havalandırıcılarının kavitasyon üzerindeki etkisi araştırılmıştır. Bu amaçla seçilen bir dolusavağı modelinin üç boyutlu sayısal modeli hazırlanıp farklı Froude sayılarında Hesaplamalı Akışkanlar Dinamiği (HAD) analizleri gerçekleştirilmiştir. Daha sonra farklı bir havakandırıcı tipi olan alttan alışlı havalandırıcı modele yerleştirilerek orijinal havalandırıcılara benzer şekilde HAD analizleri gerçekleştirilmiştir. HAD analizlerinden elde edilen sonuçlar birbirleriyle kıyaslanmış ve her iki havalandırıcının da kavitasyon hasarından yeterince korunduğu sonucuna varılmıştır. Elde edilen sonuçlar ayrıca literatürdeki farklı tip ve yöntemlerle elde edilen havalandırıcı sonuçlarıyla karşılaştırılmıştır.

Keywords

Dolusavak, Flow-3D, Havalandırıcı, Kavitasyon, Sayısal Analiz, HAD

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