1. a National School for Water and Environmental Engineering of Strasbourg (ENGEES), ICube (University of Strasbourg, CNRS, INSA of Strasbourg, ENGEES), Mechanics Department, Fluid Mechanics Team , ENGEES, 1 quai Koch BP 61039, 67070 , Strasbourg cedex , France
2. b National School for Water and Environmental Engineering of Strasbourg (ENGEES), ICube (University of Strasbourg, CNRS, INSA of Strasbourg, ENGEES), Mechanics Department, Fluid Mechanics Team , ENGEES, 1 quai Koch BP 61039, 67070 , Strasbourg cedex , France E-mail: