A cavitating-flow calculation method is presented, based on the panel technique with minimization of a certain vector characterizing the discretion error which may become important under cavitating conditions. Several practical examples are presented: partial cavitation on an isolated foil, cavitation behind a blunt-ended body, and the problem of two cavities around an axisymmetrical body. In the case of partial cavitation, the Joukowski condition and tangential outlet condition can be satisfied by the form of the error vector. The cavity-wake modelling problem is not extensively dealt with. It is shown, however, that in order to obtain a satisfactory cavity length/cavitation number ratio, it is probably necessary to introduce a displacement thickness behind the near wake of the cavity which does not close on the body according to a separated flow scheme analagous to the wake, as introduced previously by Yagamuchi & Kato (1983). The method is shown to be capable, after a few minor modifications, of dealing with the case of bodies with a rounded rear edge. Even so, the advantage is essentially didactic as the problem of predicting the position of separation points is not treated. The problem of two cavities around axisymmetrical bodies has a more obvious practical interest. The nonlinear closure condition of each cavity is exactly satisfied by an iterative resolution scheme in which allowance is made for the presence of an axial gravity field.

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