CuO-H2O nanofluid hydrothermal analysis in a complex geometry is presented using CVFEM. Brownian motion influence on properties of CuO-H2O is considered. In order to eliminate pressure gradient source terms, vorticity stream function method has been applied. The homogenous model has been utilized for simulation of H2O-CuO nanofluid. Effects of number of undulations, volume fraction of nanofluid and Rayleigh number on hydrothermal treatment are examined. Results indicate that temperature gradient enhances with augment of number of undulations. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.