PSI - Issue 2_A

Şebnem Özüpek et al. / Procedia Structural Integrity 2 (2016) 2623 – 2630 S¸ebnem O¨ zu¨pek and C¸ ag˘rı Iyidiker / Structural Integrity Procedia 00 (2016) 000–000

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Fig. 1. BM: Mises stress contours and deformation shapes at time 27 sec ( XFEM:this study, CZM and test:Han et al. (2012)).

Fig. 2. BM: Reaction force predictions ( left:this study, right:Han et al. (2012)).

pellant, the grain, enclosed in a composite case. The inner and outer grain diameters are 202mm and 400mm, respectively. The case thickness is 6mm. Material Models The SRM consists of two di ff erent materials. The case is made of a fiber reinforced plastic and was modeled as a linear elastic material. The grain is a nonlinear viscoelastic material. The constitutive model used for the propellant combines viscoelasticity with a hyperelastic model. Material properties for the case and the grain were taken from a previous study H.C. Yıldırım (2011). For the propagation analysis, traction - separation damage model shown in Figure 3 was used. The T-S model is defined with two parameters: t c , the maximum stress value which determines the crack initiation, and G c , the fracture energy which is the energy needed for complete separation of the new crack faces.