Hydrodynamic Simulations of Irradiated Secondary Stars in Dwarf Novae

We investigate the possibility of a mass transfer enhancement during outburst in dwarf novae. We present here the first two-dimensional hydrodynamic simulations of the surface flows in the secondary, driven by the strong inhomogenous heating of the atmosphere during an outburst. We also discuss the possibility that the direct heating of the L1 point by the disc rim contributes to the mass transfer enhancement.