Numerical study of influence of biofuels on the combustion characteristics and performance of aircraft engine system

• Influences of biofuels properties on combustion characteristic are explored.
• Effects of biofuels on cycle parameters of aircraft engine are discussed.
• Viscosity and caloric value are key factors affecting combustion of biofuels.
• NO emission becomes lower when biofuels with low caloric value is adopted.
• The performance of aircraft engine becomes worse for biofuels with low caloric value.

The atomization and combustion flowfield of the combustion chamber with swirl-nozzle were simulated using different biofuels; the thermodynamic cycle of the aircraft engine system were also analyzed, influences of biofuels on the combustion characteristics and performance of aircraft engine system were explored. Results show that viscosity and caloric value are key factors affecting the atomization and combustion characteristics of biofuels, and then dominate the distribution of the temperature and NO concentration. Due to the characteristic of low viscosity and low caloric value for biofuels adopted, the biofuels accumulate near the head of combustion chamber, and the corresponding NO emission is lower than that it has for conventional kerosene. When biofuels with low caloric value are used under the operation condition which is same as the condition for the conventional kerosene, lower turbine inlet temperature, lower thrust and higher specific fuel consumption would be achieved for the aircraft engine.