FINITE ELEMENT ANALYSIS OF THIN WALLED PRESSURE VESSELS

Abstract

In this study thin walled pressure vessels made from two different materials refered in ASTM standarts were analysed under pressure. Two and three dimensional finite element models were constructed by Ansys 9.0, three dimensional model was studied for two different designs. Failure analysis was performed with stress resultants. Burst pressures and critical areas were obtained by using maximum stress criteria. Failure resultants were compared with Von Mises yield criteria and analytical results of standarts. It was found that finite element models, design criterias and material properties are effective tools for analysis. The burst pressure results based on finite element analysis were found higher than the results of analytical solutions based on the standarts .

Keywords

• Thin walled pressure vessels, Burst pressure, Failure analysis.

iNCE CiDARLI BASINÇLI TÜPLERiN SONLU ELEMANLAR YÖNTEMiYLE ANALiZi

Öz

Bu çalısmada ince cidarlı basınçlı tüplerde ASTM standartlarında belirtilen iki farklı çelik için basınç etkisi altında gerilme analizi yapılmıstır. İki boyutlu ve üç boyutlu sonlu elemanlar modelleri Ansys 9.0 yardımıyla olusturulmus, üç boyutlu model tasarım yönünden iki farklı sekilde incelenmistir. Maksimum gerilme kriteri yardımıyla patlama basınçları bulunmus, tüp üzerindeki hasarlı bölgeler belirlenmistir. Hasar sonuçları Von Mises kriteri sonuçları ve standartlardan elde edilen analitik sonuçları ile karsılastırılmıstır. İnce cidarlı basınçlı tüplerin sonlu elemanlar analizinde olusturulan modelin, tasarımsal etkilerin etkinligi ortaya çıkmıstır. Analize dayalı patlama basıncı sonuçları standartlardan elde edilen analitik sonuçlara göre daha yüksek bulunmustur.

Anahtar Kelimeler

• İnce cidarlı basınçlı kaplar, Patlama basıncı, Hasar analizi.

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