**Preface to "CFD Modelling and Simulation of Water Turbines"**

Numerical simulations for the performance prediction of water turbines are becoming a standard tool in the engineering practice. This book is focused on the modelling and simulation of water turbines for both conventional and unconventional hydropower energy. The scope of this book includes state-of-the-art Topics in the field of hydropower energy production, such as: modelling of pump-turbines, simulation of horizontal and vertical axis turbines for hydrokinetic applications and modelling of hydropower plants. Finally, this book promises to be a good reference for researchers and graduate students alike who share an interest in reliably predicting the performance of water turbines based on numerical simulations.

> **Santiago Lain and Omar Dario Lopez Mejia** *Editors*
