Numerical Simulation and Survey of Heat Transfer of Flow Mixing in a Lobed Mixer of a Turbofan Engine

Mixer, a component of turbofan engines is used to mix bypass cold flow with central body hot flow. In this study, the flow passing through the lobed mixer of a high bypass turbofan engine are simulated. First phase of the study was validation of the simulation method. The next phase was assessing the effect of heat transfer and mixing of hot and cold flows in the high bypass turbofan engine mixer. The results show that by raising the mixing length, the admixture of cold and hot flow increases regularly (layered) and the total temperature diminish. Alloy in mixer lobes plays the greatest role in this cooling process. Mixer successfully lowers 800 Kelvin temperature to of 340 Kelvin. The axial velocity of hot flow before entering the lobes is 210 m/s, decrease while passing the mixer lobes, re-boost in a short distance between the nozzle and the central body, eventually decreasing during flow exit. Besides, the transverse velocity generated deep inside the lobes have a substantial role in flow mixing.