Multiple Surface Cracks in Pressure Vessels
نویسنده
چکیده
Abstract-An alternating method, in conjunction with the finite element method and a solution for multiple coplanar elliptical cracks in an intinite solid, is used to determine stress intensity factors for semi-elliptical surface flaws in cylindrical pressure vessels. The solution technique for multiple cracks in an infinite body has recently been developed by the prese.nt authors which implements a well-known analytical solution for a single crack in an infinite body. The present finite element alternating method leads to a very inexpensive procedure for routine evaluation of accurate stress intensity factors for flawed pressure vessels. Numerical examples are presented for the situation of two equal surface cracks in a pressure vessel. Comparison is made between these results and the procedure for multiple cracks in the ASME Boiler and Pressure Vessel Code.
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