Atıl Erdik, Vahdet UÇAR

On Evaluation and Comparison of Blast Loading Methods Used In Numerical Simulations

Anahtar Kelimeler:

Patlama yükleri, CONWEP, Arbitrary Lagrangian Eulerian (ALE) yöntemi, LS-DYNA, Sayısal benzetim, Çözüm ağı hassasiyeti

On Evaluation and Comparison of Blast Loading Methods Used In Numerical Simulations

It is crucial to assess the dynamic behavior of structures exposed to blast loading in order to improve the integrity and survivability. Numerical simulations are widely used to predict the response of structures under blast loading. A commercial nonlinear finite element code, LS-DYNA provides three blast loading methods: Empirical blast modeling technique CONWEP, Arbitrary Lagrangian Eulerian technique (ALE), and hybrid CONWEP - ALE technique. In this study, an experimental testing of a flat plate subjected to blast loading is modeled using these three blast loading methods in LS-DYNA. Mesh resolution study of ALE formulation is conducted to determine the influence of element mesh size on predicting blast loading effects that is converted through fluid structure interaction algorithm from Eulerian to Lagrangian type of elements. It is drawn a comparison between peak pressures calculated in simulations and maximum dynamic deformation measured in the field test. Finally, the discussion and conclusion are provided.

Keywords:

Blast loading, CONWEP, Arbitrary Lagrangian Eulerian (ALE) method, LS-DYNA, Numerical simulation, Mesh sensitivity,

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