The design and performance evaluation of axial ventilator with honeycomb in the turbofan engine lubrication system

Abstract

Numerical simulations have been carried out to investigate the performance of the axial ventilator equipped with honeycomb structure. The oil /air two-way coupling model based on the Realizable k–ɛ turbulence model and the droplet impact model are proposed. Based on verifying the rationality of numerical model, characteristics of flow resistance and oil–gas separation efficiency are calculated and analyzed. The results show that the axial ventilator with honeycomb has favorable separation efficiency, which is estimated as 99.6% for the oil droplet diameter of 5 µm. The honeycomb structure has little effect on flow resistance, but plays a major role in the oil–gas separation of axial ventilator, where the contribution to the oil separation accounts for 80% at least. Besides, the increase of rotation Reynolds number enhances the centrifugal force, resulting in the increase of separation efficiency, while the increase of nondimensional mass flow rate and environmental temperature reduce the residence time of oil droplets in the axial ventilator mainly, resulting in the decreasing of separation efficiency.

Keywords

Axial ventilator honeycomb structure oil droplet–wall interaction flow resistance separation efficiency

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