COMBUSTION CHARACTERISTICS OF STEADY AND INTERMITTENT HIGH PRESSURE SPRAYS IN A GAS TURBINE COMBUSTOR

An experimental investigation has been carried out to study combustion characteristics and the emissions of steady and intermittent high pressure sprays in a gas turbine combustor. A typical diesel injection system with a pintle type injector is used to supply an intermittent spray through a gas turbine combustor. An accumulator pressurized reservoir has been installed in the injection system to supply a steady spray. Measurements of temperature distributions and species concentrations have been carried out for pressures ranging from 1 to 20MPa for both intermittent and steady spray flames.

Obtained results show that the injection pressure of liquid fuel sprays has an important role on spray characteristics, spray combustion and emission formations processes in the gas turbine combustion. Sut increasing the pressure, the Sauter mean diameter of the spray droplets is decreases and the combustion process is considerably accelerated. A remarkable decrease occured in the nitric oxide concentration in the combustion products in the case of intermittent spray flame compared with the case of steady spray flame.