THE IMPACT OF WATER INJECTION WITHIN A GAS TURBINE’S INTAKE, AT ITS STARTING ON THE TEST BENCH

ABSTRACT

Generally, for co-generative applications, the gas turbine is set to work in standard conditions, defined as ISO: 15 0C, 1.013 bars and 60 % relative humidity. During summer, the air temperature increases and its density decreases thus leading to the reduction of the inducted air. As a direct consequence, the power at the turbine’s shaft will decrease since it is proportional with the inducted air. Also, the environment regulations are more and more restrictive, thus leading to the necessity of researches regarding pollutants and their reduction even at the starting of the co-generative group. Thus, water injection within a gas turbine’s intake, besides the increase of power, also may lead to the reduction of NOx emissions. On COMOTI’s test bench, placed in Bucharest on Militari industrial platform, experiments have been made related to water injection within a TA2 gas turbine intake. TA2 gas turbine was made from TV2-117A gas turbine which was modified by the institute’s specialists to work on natural gas instead of liquid fuel. Since the test bench is placed nearby the residential area, the influence of water injection on temperatures distribution on the turbine-chimney path, power increase, NOx reduction and impact at industrial/residential interface, have been analysed. Water injection within gas turbine’s intake, working at its idling, led to a NOx reduction of 7 ppm and, based on the drawn dispersion charts, at industrial/residential interface the values are way below the ones set by the in force regulations.

Keywords: gas turbine, water injection, test bench, emissions, dispersion charts