Dynamic fracture research based on XFEM and its application on discharge valve guard of hydrogen compressor

The structural safety analysis under complex environment and load conditions is at the leading edge of engineering researches. The dynamic fracture research based on Extended Finite Element Method (XFEM) is probed into in the paper, and the modeling principle of strong discontinuities based on XFEM is applied to dynamic fracture mechanics to overcome the difficulty of defining meshes around crack tip without remeshing. XFEM-based dynamic interaction integral method is developed to reduce the calculation error caused by the non-matching meshes in the crack-tip area. Typical examples, the edge crack plate and central inclined crack plate under Heaviside function type impact loads, are taken to validate effectiveness of the method. Furthermore, as an engineering application, a valve guard subjected to impact load is simulated using the method, and numerical simulation results suggest that the valve guard is relatively safe under static load without hydrogen environment, but the real operating conditions with both hydrogen environment and dynamic load, will lead to higher brittle fracture risk for the valve guard.