This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.In this paper, numerical modeling of Joule heating in electroosmotic flows is described in some detail. The finite element method is used for the spatial discretization along with the characteristic based split (CBS) time discretization. A new non-dimensional scaling is also introduced. In addition to standard problems of micro channel flows, flow and heat generation in a T-mixer are also discussed in this paper
