ABSTRACT
As in other fields of engineering, in hydraulic engineering numerical computation methods are used more and more for studying the physical phenomena involved and for solving practical problems. Here, and in fact in the entire book, hydraulic engineering always includes environmental engineering and hydraulics includes environmental fluid mechanics, albeit restricted to the wet environment. With the increasing computer power and the availability of advanced numerical methods, increasingly more complex and practically realistic problems can be solved by numerical methods. A difficulty in obtaining reliable predictions is the fact that almost all flows in hydraulics, whether geophysical or man-made flows, are turbulent, except for groundwater flows. The unsteady irregular eddying motion associated with turbulence increases greatly the momentum, heat and mass transfer and hence has significant influence on all aspects of the flow and associated phenomena such as temperature, concentration distributions and sediment transport etc., as will shortly be outlined in some detail. Hence, in any successful computation of flow and associated phenomena, a realistic simulation of the effect of turbulence is important. This book deals with an advanced, powerful method for simulating turbulence, namely the Large Eddy Simulation (LES), which, also for practical problems in hydraulics, can be seen as the method of the future.
