Vortex dynamics around a solid ripple in an oscillatory flow T. Sand Jespersen, J. Q. Thomassen, A. Andersen and T. Bohr Eur. Phys. J. B, 38 1 (2004) 127-138 Published online: 20 April 2004 DOI: 10.1140/epjb/e2004-00108-y