Modelling
Analysis and
Research in
Turbomachinery and
Energy
Systems
The expertise in this field was gained thanks to the intense study of the literature and the participation to several research projects of high scientific content. The contribution to these projects was mainly aimed at supporting the design and the analysis of the operation of combustors and burners using CFD simulations. However, the need to strongly validate numerical results encouraged the direct participation to the experimental activities and promoted the development of skills also in the analysis of experimental data and test schedule. Research projects were performed in collaboration with ENEL Spa, Nuovo Pignone Oil&Gas (GE), Italian Institutions (Hydrogen Park, University of Florence, Research Institute on Combustion of Naples), Baxi Spa and BSG Boilers Spa.

The topic and the aim of the main projects in which the MARTES Group was involved and specific contributions are listed in the following table.
a) Simulation of combustion instabilities in a 10 MW industrial boiler. Time history of pressure in the combustion chamber from ignition (above) and temperature field under unstable operation at 38 Hz (below)
COMBUSTORS AND BURNERS

PROJECT AIM
CONTRIBUTIONS
Design of new configurations of burners for domestic boilers (2 years)
Design, CFD simulations (isothermal and reactive),
participation and support to full-scale tests of prototypes
Design and test of 10MW gas turbine combustors for non-premixed combustion of hydrogen with maximum NOx emissions of 200ppm@15%O2 (4 years)
Unsteady CFD simulations aimed at verifying the combustion stability of prototypes and modelling the potential thermoacoustic instabilities. Steady CFD simulations for the calculation and the analysis of the internal flow field, the liner wall temperatures, the temperature distribution at the combustor discharge and NOx emissions. Participation to full-scale full-pressure experimental tests of prototypes
Design and test of scaled combustors for premixed combustion of hydrogen (3 years)
Unsteady CFD simulations aimed at verifying the combustion stability of prototypes and modelling the potential thermoacoustic instabilities. Steady CFD simulations for the calculation and the analysis of both the isothermal and reactive flow field
Reduction of pressure fluctuations in 10 MW industrial boilers (1 year)
CFD simulations (isothermal and reactive) and redesign support
b) Experimental pressure spectrum used to validate CFD results shown in Figure a)
c) Temperature field in a 10 MW gas turbine combustor (hydrogen operation - full load)
d) Calculated and measured wall temperatures along the liner wall (hydrogen operation - full load)
f) Flame structure on the surface of a small burner for domestic boilers
e) Calculated and measured radial velocity of the isothermal flow through a dilution hole of a gas turbine combustor