The impact of circumferential casing grooves on rotating instability is first assessed for both design and part speed operations in a transonic axial compressor, with the purpose of developing the next generation casing treatments for vibration control. Multi-passage time-resolved computations are performed to capture the origination and propagation behavior of the instability for cases with and without casing grooves. Probed pressure signals in different passages show a nonsynchronous fluctuation of tip flow. It proves tip leakage vortex and its self-excited oscillation is responsible for this type of inconsistence, regardless of the compressor operation speed. Although flow separation on blade suction surface and the consequent shedding vortex contributes to another origin of instability, the resulted flow appears to be consistent. Casing grooves are able to enhance the synchronization by greatly suppressing both tip leakage vortex oscillations and the intermittently shedding separation vortex, especially in the front part of blade passage. Both types of instability are constrained in several separated axial scope by casing grooves, which essentially increase the damping of flow oscillations. Thus, further improvement of casing treatment design can be expected if the axial transport of the instability in the tip region is restrained more efficiently, for both extending stall margin and enhancing aerodynamic stability.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    The impact of circumferential casing grooves on rotating instability in a transonic axial compressor


    Contributors:
    Ye, Shubo (author) / Zhao, Qingjun (author) / Zhou, Xiaoyong (author) / Xi, Guang (author) / Xu, Jianzhong (author)


    Publication date :

    2019-06-01


    Size :

    26 pages




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English