Abstract: The primary focus in this presentation is the numerical analysis of a surge tank-pipeline junction.The response to a pressure pulse is provided by a characteristics-like method for two-dimensional flow. Exact analytical solutions are presented and compared with the numerical results for cases of a sudden area expansion and a sudden area contraction in order to demonstrate the validation of the method.Some results are also provided of a comparison between the one-dimensional and two-dimensional flow methods for transients at a sudden area enlargement and surge tank-pipeline junction in a two-dimensional flow field.