Experimental investigation of a counter-rotating compressor with boundary layer suction

et al. 2020

JAFM

To control secondary flow effects and enhance the aerodynamic performance of the compressor, the flow control effects of the flow suction at the endwall with different circumferential positions and at the blade tip were numerically investigated in the cantilever stator of an axial single-stage transonic compressor. The main purpose was to gain a better understanding of the application of boundary layer suction and the associated control mechanisms in the cantilever stator. The studies show that the optimal position of the endwall suction slot should be located up the stator blade, in terms of the leakage flow structures and the blade tip unloading effect. In addition, the flow control effects of the suction at the blade tip on leakage flow upstream is better than that of the endwall flow suction with the same structure. Further, the studies of compressor aerodynamic performance curves illustrate that the efficiency and pressure ratio is increased by 0.34% and 1.09% at the peak efficiency point, and are increased by 0.39% and 0.14% at the near stall point, respectively.

Section: Introductionmentioning

confidence: 99%

Impact of Boundary Layer Suction on Clearance Leakage Flow in a Cantilever Stator of Transonic Compressor

Zhang

et al. 2020

JAFM

“…The BLS technology was applied to the surface of compressor stator blade by Loughery et al (1971), which greatly enhanced the ability of airflow turning and efficiency of the compressor. Subsequently, a large number of numerical and experimental studies showed that the application of BLS technique could effectively control boundary layer separation of the blade SS and corner (Guo et al 2010;Shi et al 2015a). Lu et al (2016) inhibited the development of the TLF and TLV of a compressor cascade with gap by using the blade tip suction scheme (BTS) because the onset position of TLV shifted downstream.…”

Section: Introductionmentioning

confidence: 99%

Numerical Research on the Impact of Axial Position of Endwall Suction Slot on Tip Leakage Flow

Zhang

Rehman

et al. 2020

JAFM

In order to reduce the adverse effect of the tip leakage flow of cantilever stator on compressor performance, the impact of the axial position of endwall streamwise suction slot on tip leakage flow was numerically studied. The study on the overall performance of the compressor and the details of the flow field near the stator end region with and without suction showed that all suction schemes could weaken the tip leakage flow intensity to a certain extent, and the flow control effect was gradually enhanced with the increase of the suction flow rate. In the case of small suction flow rate, for example, 0.5%, the short slot schemes can improve the overall efficiency of the compressor by about 0.5%, which is more advantageous than the long slot scheme, and the overall efficiency improvement of the latter is about 0.3%. The advantage of the long slot scheme in flow control is reflected in the case of large suction flow rate, that is, 1.0%, which may improve the overall efficiency of the compressor by about 0.96%. The axial position of suction slot has a significant influence on flow control effect of the tip leakage flow. Compared with the downstream suction, which only modified the flow field by reducing the blocking effect generated by tip flow vortex, the upstream suction could better control the tip leakage flow by restraining the development of the initial stage of the leakage vortex. Besides, the endwall suction scheme with a full chord length slot has the greatest impact on the passage vortex, its effect on modifying the flow field near the end zone was determined by the combinatorial action of the enhancement of the passage vortex and the attenuation of the leakage vortex.

“…So far the studies about suction mainly concentrate on the control of the boundary layer separation on the blade SS (Song et al 2006;Guo et al 2010;Shi et al 2015b) or the three-dimensional (3D) separation in the hub corner (Sachdeva et al 2011;Pönick et al 2013;Guo et al 2008;Marsan et al 2015). Apart from some researches about the effects of bleeding system on the compressor performance (Leishman et al 2007a(Leishman et al , 2007b(Leishman et al , 2007cGrimshaw et al 2015Grimshaw et al , 2016, there are only several investigations of suction technique on the control of TLF to improve the compressor performance and stability (Gümmer et al 2008;Dobrzynski et al 2008;Shi et al 2015a). It is found that the flow fields in the tip region and operating range can be improved by the suction on the casing.…”

Section: Introductionmentioning

confidence: 99%

Control of Tip Leakage Flow in Axial Flow Compressor Cascade by Suction on the Blade Tip

Mao

Tang

2018

JAFM

One of the important ways of improving axial compressor performance is to control the tip leakage flow near the endwall region. Numerical computations were conducted to investigate the impact of blade tip suction on the axial compressor cascade performance in current paper. Three suction schemes located on the blade tip with different chordwise coverage were investigated in total. The results show that the cascade overall performance can be effectively enhanced by the proper suction scheme on the blade tip and the best scheme should be arranged at slightly downstream of the onset point of the tip leakage vortex (TLV). The control effectiveness and mechanisms are different for the different suction schemes. For the suction scheme covering the starting point of TLV, the onset point of TLV is shifted downstream, while an additional induced leakage flow near the blade leading edge is generated resulting in the increase of mixing loss. It is more effective when the structure of the main TLV is destroyed and divided into different parts by applying the blade tip suction arranged slightly behind the onset point of TLV. In addition, the blade loading is redistributed near the blade tip after the blade tip suction and the total pressure loss caused by the suction slots should also be considered in the design process.