Research On Axial Breather With Tangential Air Inlet

Based on previous research on axial breather of aeroengines, this paper analyzes theinfluence of tangential air inlet on flow resistance and separation coefficient of axial breather.The method of numerical simulation is used in the analysis with the calculation domain of athree-dimensional model. By altering structure of the axial ventilator, this paper compares andexplains the factors attributing to flow resistance and separation characters. Optimization ofthe axial breather is also studies, which is deemed to be helpful to later research.The fact that the separation coefficient is relatively low on the segment from annularcavity to inlet has been found in previous research. Theoretically, the main reason leading tothis low coefficient is the excessive low centripetal acceleration, which can be improved byusing tangential inlet. Further study is also conducted to determine which eccentricity is morereasonable.Using DPM model of CFD, models with different eccentricities are simulated under thesame operating condition. Simulation of the same model under different operating conditionsis also analyzed and compared. Conclusions show that tangential inlet has no distinct impacton the resistance character of the axial breather, while significantly affects the separationcoefficient. For the same structure, separation coefficient is higher as eccentricity increaseswithin a certain range. However, eccentricity would have a much smaller influence onseparation coefficient after a specific peak value. The change of eccentricity does not have anobvious impact on flow resistance of the axial ventilator, which only shows a slight augmentwhen eccentricity is increasing.