Influence of blade tip cutting on axial compressor aerodynamic performance

Abstract

The purpose of this article is to numerically investigate the function of blade tip cutting on axial flow compressors. The subject of this article is a subsonic compressor stage built and tested by Northwest Polytechnic University. The effect of cutting material from the blade pressure side is first analysed as an isolated rotor, and then in the environment of a stage with a downstream stator. The tool used for simulation is commercial computational fluid dynamics package of NUMECA.The numerical results show the possibility of increasing the rotor/stage pressure ratio and improve rotor efficiency by finding the right cut. The most significant effect of blade tip cutting is that it redistributes the load along blade span. When the adjusted load shape now fits with the downstream stator, the advantage of blade tip cut can be magnified; on the contrary, if the shape is not compatible with the downstream load, then the configuration that favours the performance of the rotor may deteriorate than that of the stage.This study also indicates that the blade tip cutting technique is rather case-dependent and that the performance of the cut blade is very sensitive to the shape of blade leading edge. Positive effect will only be significant when the cut is tailored to benefit both the local rotor flow field and the downstream flow field.

A Proper Shape of the Trailing Edge Modification to Solve a Housing Damage Problem in a Gas Turbine Power Plant

“…Contrary to this, model B had the higher pressure ratio in a larger area than the other models. Figure 6 also depicts that the modifications of the CB were strongly influential on the pressure around the root area, as reported in [1,15]. For further analysis, the results in Figure 6 were normalized with the pressure ratio of model A at the same positions and then reported in Figure 7 for blade spans of (a) 95.5%, (b) 95.8%, (c) 96.0%, and (d) 96.5%.…”

“…Finally, fatigue analysis has been employed to predict the damage, life, and safety factor of the CB [11,12]. For the AD, CFD can simulate the C l , C d , pressure, vector flow, and other variables in the compressor stage [1,[13][14][15][16][17]. From previous computer simulations, it has been indicated that inappropriate modifications can lead to inefficiency of the generator and also shorten its lifetime.…”

“…From previous computer simulations, it has been indicated that inappropriate modifications can lead to inefficiency of the generator and also shorten its lifetime. Furthermore, in [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17], most researchers focused their study on such conditions (e.g., steady rotational speed, pressure, temperature, and flow rate). Hence, the AD study has been separated from the SD investigation, because simultaneous investigations of both the AD and the SD can be very complex and troublesome.…”

Parametric study of rotor tip squealer geometry on the aerodynamic performance of a high subsonic axial compressor stage

“…1, the EJ200 [7] and the GE9X [8] engines have implemented squealered tip on more than one stage in high-pressure compressors and both engines utilize suction side squealers (SSS), while no pressure side squealer (PSS) has been found in use. Some researchers, through experiments [9][10][11] and numerical simulation [6,[10][11][12][13][14][15][16] on both compressor cascade and rotational compressor rotor, have agreed that compressor blades with SSS show better aerodynamic performance than these with flat tip, although the squealered tips used by different researchers vary greatly in geometry. Also SSS helps to improve the loading of the blade tip and therefore leads to higher pressure rise.…”

“…At the same time, tip geometry also helps to reduce tip leakage flow and improves efficiency. Lu et al [12] found that aerodynamic performance is very sensitive to the shape of squealer exit. One deliberately designed geometry of SSS, which performs well in single row simulation, causes reduction of performance when it is put into a stage simulation.…”