Multi-Dimensional Simulation Of Intake And Combustion Process In Aviation Turbo Gasoline Engine

The flow characteristics of the intake port of gasoline engine have a significant impact on gas movement in cylinder. Reasonable gas movement can optimize the formation of the mixture between air and fuel, enhance the turbulence intensity, accelerate the flame propagation velocity, and finally improve the combustion process. Thus it is necessary to study on intake and combustion process in gasoline engine. This paper carried out multi-dimensional simulation of intake and combustion process in aviation turbo gasoline engine.First, the simulation model of intake-compression-combustion process was performed using AVL FIRE. The simulation model was validated through comparison of performance parameters with prototype. For zero altitude take-off, detailed studied on the evolution rule of velocity, pressure and fuel fields with the intake valve lift changes. For 4800m altitude maximum continuous performance, detailed studied on the distribution of velocity, pressure and fuel fields.Second, the simulation model of compression-combustion process without intake process was performed using AVL FIRE. The simulation mode was validated through comparison of performance parameters with prototype. For zero altitude take-off, the distribution of velocity, pressure, temperature and fuel fields in cylinder were studied. Then studied on the effect of structure and operating parameters on combustion process of this type gasoline engine. The structure parameters include wedge-shaped combustion chamber angle, piston top shape and the locations of dual-spark. The operating parameters include ignition timing, mixture concentration and residual concentration.Finally, based on studying of single parameters, for maximum continuous performance, optimized the combustion system parameters using the Orthogonal Method with active power as its optimization objective. The results showed that the most significant parameters impact active power were mixture concentration and residual concentration, followed by the wedge-shaped combustion chamber angle.