• cfd
• enel
• fluent
• xdem

Nowadays, biomass materials as a type of renewable energy source have attracted much interest with the aim to decrease fossil fuel usage due to ecological and economic benefits. The main objective of the present Master’s thesis is to study biomass conversion performance inside the combustion chamber of a 16 MW geothermal steam superheater, which is part of the Enel Green Power “Cornia 2” power plant. This is firstly done employing the eXtended Discrete Element Method (XDEM), a code developed at the University of Luxembourg which consists of a hybrid four-way DEM-CFD coupling approach that considers the solid biomass particles as discrete elements interfaced via heat, mass and momentum transfer to the surrounding gas as continuous phase. Due to the high computational cost required, a two-dimensional domain has been set up in this case. A complete framework of species distribution and the characteristic thermo-fluid dynamic parameters in the gas phase is then obtained interfacing the output data of the aforementioned model in a three-dimensional CFD simulation of the freeboard. This two-step approach has been applied to three different experimental cases conducted by EGP with the aim to improve combustion efficiency. The consistency of the numerical results with the real system performance is discussed in this work, allowing to deduce the potentialities and the limits that distinguish this approach.