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Journals / Isı Bilimi ve Tekniği Dergisi / 2009 / Cilt: 29 - Sayı: 1

Üç boyutlu silindir arkasındaki zamanla değişen türbülanslı girdap yapısı

Unsteady turbulent vortex structure downstream of a three dimensional cylinder

Selin ARADAG
Pages
91–98
Publication Date
2022-10-18
DOI
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

The energy content of the POD modes reveals that only four spatial modes have 98% of the total energy in the flow and are enough to represent the flow.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:This study examines the near wake behavior of the turbulent, unsteady flow over a three dimensional circular cylinder at Re=20,000, based on cylinder diameter, computationally.
📊
Key Findings & Data:From a CFD perspective, this work assesses the capability of unstructured grids and large eddy simulations without a subgrid scale model, for the prediction of flow behavior at transitional Reynolds numbers for the time-dependent flow over a circular cylinder.
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Conclusion & Impact:The energy content of the POD modes reveals that only four spatial modes have 98% of the total energy in the flow and are enough to represent the flow.
🔬Design:Modeling & Simulation
📍Scope:Comprehensive Sample
⚙️Variables:Domain Parameters

Abstract

This study examines the near wake behavior of the turbulent, unsteady flow over a three dimensional circular cylinder at Re=20,000, based on cylinder diameter, computationally. From a CFD perspective, this work assesses the capability of unstructured grids and large eddy simulations without a subgrid scale model, for the prediction of flow behavior at transitional Reynolds numbers for the time-dependent flow over a circular cylinder. Proper orthogonal decomposition is also applied to the computational results in order to investigate the flow structure further and examine the energy content of the turbulent flow at hand. The results of the computations are in close agreement with the experimental results in literature. The energy content of the POD modes reveals that only four spatial modes have 98% of the total energy in the flow and are enough to represent the flow.

Özet

Bu çalışmada üç boyutlu silindir çapına gore hesaplanan Reynolds sayısı 20,000 olan silindir üzerindeki zamana bağlı değişen türbülanslı akış sayısal olarak incelenmiştir. Sonuçlar litern atürdeki deneysel çalışmalarla kıyaslanmıştır. Hesaplamalı akışkanlar dinamiği (HAD) açısından bakıldığında çalışma, düzensiz ağların ve Large Eddy Simulation yönteminin alt ağ yöntemi kullanmadan laminerden türbülanslı akışa geçiş Reynolds sayılarına denk gelen bir akış rejimi için kullanılabilirliğini test etmektedir. Sayısal sonuçlara dikgen ayrıştırma yöntemi uygulanarak eldeki türbülanslı akışın enerji dağılımı ve akış özellikleri ayrıntılı olarak incelenmiştir. Sayısal analiz sonuçları literatürdeki deneysel çalışmaların sonuçlarıyla uyum içerisindedir. POD kip enerjilerini gösteren grafikler, sadece dört mekansal kipin toplam enerjinin %98’ini oluşturduğunu ve akışı modellemek için yeterli olduğunu göstermektedir.

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Cite This Article

ARADAG, S. (2022). Üç boyutlu silindir arkasındaki zamanla değişen türbülanslı girdap yapısı. Isı Bilimi ve Tekniği Dergisi, Cilt: 29 - Sayı: 1, 91–98. https://ajindex.com/articles/542622

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