saujs Sakarya University Journal of Science 2147-835X Sakarya University 10.16984/saufenbilder.357629 Mechanical Engineering Makine Mühendisliği On Evaluation and Comparison of Blast Loading Methods Used In Numerical Simulations Erdik Atıl Otokar, Otomotiv ve Savunma Sanayi A.Ş Uçar Vahdet Department of Mechanical Engineering, Sakarya University, Turkey 10 01 2018 22 5 1385 1391 11 24 2017 04 06 2018 Copyright © 1997, Sakarya University Journal of Science 1997 Sakarya University Journal of Science

It is crucial to assess thedynamic behavior of structures exposed to blast loading in order to improve theintegrity and survivability. Numerical simulations are widely used to predictthe response of structures under blast loading. A commercial nonlinear finiteelement code, LS-DYNA provides three blast loading methods: Empirical blastmodeling technique CONWEP, Arbitrary Lagrangian Eulerian technique (ALE), andhybrid CONWEP - ALE technique. In this study, an experimental testing of a flatplate subjected to blast loading is modeled using these three blast loadingmethods in LS-DYNA. Mesh resolution study of ALE formulation is conducted todetermine the influence of element mesh size on predicting blast loadingeffects that is converted through fluid structure interaction algorithm fromEulerian to Lagrangian type of elements. It is drawn a comparison between peakpressures calculated in simulations and maximum dynamic deformation measured inthe field test. Finally, the discussion and conclusion are provided.

 Blast loading CONWEP Arbitrary Lagrangian Eulerian (ALE) method LS-DYNA Numerical simulation Mesh sensitivity Patlama yükleri CONWEP Arbitrary Lagrangian Eulerian (ALE) yöntemi LS-DYNA Sayısal benzetim Çözüm ağı hassasiyeti [1] G. Randers-Pehrson, K.A. Bannister, Airblast Loading Model for DYNA2D and DYNA3D, in: ARL-TR-1310, US Army Research Laboratory, Aberdeen Proving Ground, 1997. [2] C.N. Kingery, G. Bulmash, Airblast parameters from TNT spherical air burst and hemispherical surface burst, in, Ballistic Research Laboratory, Aberdeen Proving Ground, Aberdeen, MD, 1984. [3] N.F.E.C. U.S. Army Corps of Engineers, Air Force Civil Engineering Support Agency, Design and analysis of hardened structures to conventional weapons effects, in: Supersedes TM 5-855-1/NAVFAC P- 1080/AFJAM32/DSWA DAHSCWEMAN-97 August 1998, Department of the Army, US Army Corps of Engineers and Defense Special Weapons Agency, Washington, DC, 2002. [4] J.L.C. C. W. Hirt, T. D. Butler, A Lagrangian method for calculating the dynamics of an incompressible fluid with free surface, Journal of Computational Physics, 5(1) (1970) 103-124. [5] C.W. Hirt, An arbitrary Lagrangian-Eulerian computing technique, in: Proceedings of the Second International Conference on Numerical methods in Fluid Dynamics Lecture Notes in Physics, 1971, pp. 350-355. [6] T.P. Slavik, A Coupling of Empirical Explosive Blast Loads to ALE Air Domains in LS-DYNA, in: 7th European LS-DYNA Conference, Livermore Software Technology Corporation, Salzburg, Austria, 2009. [7] Z.S. Tabatabaei, J.S. Volz, J. Baird, B.P. Gliha, D.I. Keener, Experimental and numerical analyses of long carbon fiber reinforced concrete panels exposed to blast loading, International Journal of Impact Engineering, 57 (2013) 70-80. [8] J.O. Hallquist, LS-DYNA keyword user’s manual, in, Livermore Software Technology Corporation, California, U.S.A., 2007. [9] B.M. Dobratz, P.C. Crawford, LLNL Explosive Handbook "Properties of Chemical Explosives and Explosive Simulants", in, Lawrance Livermore National Laboratory, Livermore, California, 94550, 1985. [10] J.O. Hallquist, LS-DYNA theory manual, in, Livermore Software Technology Corporation, 2006.