Investigation On The Flow And Atomization Characteristics Of Centrifugal Nozzle Under Physical Parameters

The centrifugal atomizing nozzle is widely used in the aviation gas turbine,the ground gas turbine and other combustion equipment,and the nozzle has wide fuel flow regulation range and good atomization quality,And the combustion chamber has a better ignition performance and a wide oil-lean flame-out range.In addition to the structural parameters of the nozzle,the working environment of the nozzle and the physical and chemical properties of the fuel oil will have a great effect on the atomization characteristics.In order to obtain the influence of external physical parameters on the internal flow characteristics and atomization characteristics of the centrifugal nozzle,the influence of fuel temperature,injection environment temperature and pressure on the internal flow and atomization characteristics of the centrifugal nozzle was studied experimentally and numerically.The atomization characteristics under the fuel temperature in the range of22? ? 50? and the fuel pressure in the range of 0.3MPa ? 1.5MPa were tested in the experiment.With the FLUENT used,the atomization characteristics under the fuel temperature from-50? to 50? and the fuel pressure in the range of 0.3MPa?1.5MPa were numerically simulated in the ambient condition.At the same time,when the injection pressure is 4MPa,the fuel temperature is 100?,the ambient temperature from-50? to 400?and the ambient pressure in the range of 0.1MPa ? 3MPa were numerically simulated.The results showed that both spray cone angles are consistent with the change of temperatures.The fuel viscosity and SMD are decreases with the injection temperature.The liquid film thickness is thinner with high injection temperature.The outlet velocity and spray cone angle increase with the injection temperature;the outlet fuel volume fraction decreases with the injection temperature.when the ambient pressure is constant,the temperature increases,the air density decreases,the fuel evaporation intensifies,the gas phase fuel ratio increases,and the atomization effect increases.When the ambient temperature is constant,the environmental pressure increases,the air density increases,the crushing occurs earlier,the oil film thickness increases,and the liquid phase fuel ratio increases,although the spray cone angle and the interaction between oil and gas increase,but it is not conducive to fuel atomization.