"The overall concept of the proposed project is to improve the hydraulic efficiency of small action type turbines, through the development and application of a numerical optimization methodology, that will be validated by the construction and laboratory testing of the prototype models of Pelton, Turgo and Matrix turbines representing both action and reaction types. The methodology to be developed regards the adaptation and application of the Lagrangian Smoothed Particle Hydrodynamics model for the simulation of the flow. The application of the innovative design tool is expected to achieve an average increase in small action and Matrix hydro turbines efficiency of the order of 3 to 5%. The flow analysis software to be implemented is characterised as cost effective and capable of fast processing of multi-parametric flows, whereas the optimization strategy will be based on Evolutionary Algorithms, resulting in enhanced economic feasibility of the proposed design procedure. The investigation of three different types of small hydro turbines will demonstrate the wide application range of the new methodology and evaluate its generality. The S&T objectives of the project are: Adaptation and application of the Lagrangian Smoothed Particle Hydrodynamics model for the simulation of the flow in the action turbines to be investigated; Finding the most efficient geometry parameterization method for each of the three turbine types; Development of a multilevel optimization method based on the Evolutionary Algorithms System software; Specification, selection and set-up of the hardware and software computational platform; Finding the optimal design of the runner and other components for the three turbine types considered by applying the developed methodology; Prototype turbine models manufacturing according to the results of the design optimization procedure; Evaluation of the new design tools after thorough experimental analysis of the prototype turbine models."