Numerical and experimental studies of the electrohydrodynamic effect on natural convection in an enclosure are investigated. The governing equations of electric field, flow field and temperature field are also represented. It is found that the flow pattern is affected by the supplied voltage at the wire electrodes. Augmented heat transfer increases at low Rayleigh number and high number of electrodes. The uniform electrode arrangement along an enclosure provides maximum heat transfer when the number of electrodes is fixed. (c) 2006 Elsevier Ltd. All rights reserved.