Abstract: The effect of the shape of reservoir boundaries on the well-bore pressure response is evident. The conventional analytical methods can only be used to calculate wellbore pressure responsein regularly shaped reservoirs. In this paper, according to the theory of Boundary-Element Method (BEM), pressure transient solution in an arbitrarily shaped reservoir with any number
of irregularly shaped impermeable sub-regions is proposed by Laplace domain BEM. By using Duhamel theorem, the influence of wellbore storage and skin effect on pressure transient response is considered. Then the BEM results are compared to that of analytical methods. And pressure transient behavior
characters in arbitrary reservoir shaped are analyzed.

Key words: pressure performance, integral equation, wellbore storage, skin effect, boundary element, arbitrary shape