The development of aeroengines toward a lighter and compact structure has put forward a stringent requirement on the lubrication systems, especially on the bearing chambers which contain complex air–oil two-phase fluids. Understanding the flow characteristics is of considerable significance to ensure the cooling and lubrication effect and to improve the working reliability of the aeroengine. Hilbert–Huang transform (HHT) was used to analyze the spectral characteristics of the pressure signals in the bearing chamber, in order to establish the correlation between the energy indicator k and the flow regime. The influences of the operating conditions and lubricant physical properties on the flow regime were discussed. The findings indicate that this approach can distinguish two typical flow regimes in the bearing chamber. With the increase of oil inflow and the decrease of draft speed, the flow regime changes from homogeneous flow to stratified flow, and k shifts from high-frequency band to low-frequency band. At the same lubricant mass inflow, k shifts from low-frequency band to high-frequency band with the increase of lubricant density, and the oil film on the wall becomes thinner. As the viscosity increases, the flow resistance grows and more oil accumulates on the wall. The flow regime converts from homogeneous flow to stratified flow, with k shifting from high-frequency band to low-frequency band. In addition, higher surface tension will cause more oil agglomeration, which results in less stable two-phase flow with irregular and uneven distribution of the oil on the wall.

航空发动机向更轻，更紧凑的结构发展，对润滑系统提出了严格的要求，特别是对包含复杂的气-油两相流体的轴承腔提出了严格的要求。了解流动特性对于确保冷却和润滑效果以及提高航空发动机的工作可靠性具有重要意义。Hilbert-Huang变换（HHT）用于分析轴承腔中压力信号的频谱特征，以建立能量指示器k之间的相关性。和流动状态。讨论了操作条件和润滑剂物理性能对流动状态的影响。研究结果表明，这种方法可以区分轴承腔中的两种典型流动状态。随着进油量的增加和吃水速度的降低，流态从均匀流向分层流变化，k从高频带向低频带转移。在润滑剂质量流入相同的情况下，随着润滑剂密度的增加，k从低频频带转移到高频频带，并且壁上的油膜变薄。随着粘度的增加，流动阻力增大，并且更多的油积聚在壁上。流动状态从均质流转换为分层流，其中k从高频带向低频带转移。此外，较高的表面张力将导致更多的油团聚，这会导致两相流的稳定性降低，并且油在壁上的分布不均匀且不均匀。