HELE SHAW FLOWS WITH TIME-DEPENDENT FREE BOUNDARIES INVOLVING INJECTION THROUGH SLITS

Consider the classical Hele Shaw situation with two parallel planes separated by a narrow gap. Suppose a Newtonian fluid to be injected into this gap through straight-line slits as well as, possibly, at isolated points. We are interested in predicting the plan-view of the resultant expanding blob, or blobs, of fluid. We show that the method of solution developed earlier for dealing with such problems when the injection is only at isolated points can be adapted to yield solutions in this more general situation.