A generalised three-dimensional solver based on unstructured grid methodology has been developed for electrohydrodynamic flows. The Navier-Stokes equations with electrical field source term are solved in conjunction with the coupled electrical potential and ion charge density equations in a finite volume framework. An iterative boundary condition for updating the value of charge density on the discharge electrode is used while solving the electrical field equations. The solver is validated with available literature and the good agreement is found. © Springer India 2017.