To reveal the mechanisms underlying effect of self-circulating casing treatment with different circumferential coverage ratios on stability axial compressor, a three-dimensional unsteady numerical was hereby conducted Rotor 35. The 20%, 40%, 60%, and 80% were designed, respectively. calculated results point out that all schemes effectively expand stable working range compressor expansion is positively correlated ratio. an ratio exhibits highest stall margin improvement at 14.83%. internal...

In this paper, an adaptive sparse arbitrary polynomial chaos expansion (PCE) is first proposed to quantify the performance impact of realistic multi-dimensional manufacturing uncertainties. The Stieltjes algorithm employed generate PCE basis functions concerning geometric variations with distributions. basis-adaptive Bayesian compressive sensing introduced retain a small number significant functions, requiring fewer model training samples while preserving fitting accuracy. Second, several...

To investigate the pre-stall behavior of an axial flow compressor rotor, which was experimentally observed with spike-type stall inception, systematic experimental and whole-passage simulations were laid out to analyze internal fields in test rotor. In this part, emphases put on analyses results predicted from steady unsteady simulations, converged equilibrium solutions nearly periodic fluctuations efficiency. The objective uncover tip clearance its associated mechanism at near-stall...

In the current study, effects of a combined application between micro-vortex generator and boundary layer suction on flow characteristics high-load compressor cascade are investigated. The with special configuration longitudinal slot adopted. calculated results show that reverse region, which is considered main reason for occurring stall at 7.9° incidence, grows collapses rapidly near leading edge leads to two critical points end-wall increasing incidence in baseline. As introduced baseline...

Leading-edge tubercles are an effective method to improve the stall margin in a compressor. In existing studies on leading-edge tubercles, achieving better control all conditions is huge difficulty and challenge. Hence, new of profiling based sine attenuation functions introduced this paper. First, wavelength amplitude were varied by function study their effects compressor performance. The research reveals uniform with small large can delay incidence from 7.9° 8.8° increase it 10% compared...

The blade thickness distribution is an important geometric parameter of a compressor rotor blade. It determines the aerodynamic performance rotor, which should be carefully designed. However, manufacturing inaccuracies cause to deviate from ideal design. These deviations alter flow field near surface, affects rotor. Therefore, it great significance quantitatively investigate effects deviation on performance. In this paper, influence analyzed based transonic and uncertainty quantification...

This paper investigates the influence of boundary layer skew on flow structure, total pressure loss, and control technique numerically a high-loaded axial-flow compressor cascade. We have developed two new models respectively about loss evaluation end wall mechanism for more specific analysis. The result shows that weakens secondary delays generation passage vortex when incidence approaches 0°. results in reduction mainly (89.4%) due to relieved corner separation. However, as exceeds certain...

Casing instantaneous pressure measurements and full-annulus unsteady simulations were undertaken to analyze flow characteristics near casing at stable stall inception conditions in an axial compressor rotor, the objective was establish its linkage with process. The measured characteristic near-stall operating appearance of rotating instability (RI), which attributed activity varying frequency. A similar found simulated conditions, detailed analyses field indicated formation tip secondary...

On the basis of test results discrete axial and blade angle slot casing treatment, a new type treatment was designed for subsonic flow compressor rotor by optimizing various geometry parameters. To obtain wide operating range to minimize penalties in terms isentropic efficiency, seven configurations incorporating treatments 0, 16.6, 33.3, 50, 66.6, 83.3, 100 per cent exposures were experimentally investigated. The showed that significant improvements stall margin are possible all...

Parametric study of tip injection was implemented experimentally on a subsonic axial flow compressor to understand the underlying mechanisms stability improvement with discrete injection. Injector throat height varied from 2 6 times rotor clearance, and circumferential coverage percentage ranged 8.3% 25% annulus. Static pressure fluctuations over were measured fast-response transducers. Whole-passage time-accurate simulations also carried out help us details. The combinations traditional...

Flow variations at the inlet boundary due to compressor operational condition changes and geometric of realistic blades manufacturing variability cannot be absolutely avoided, global local performance impact which requires considered in mechanism study change aerodynamic shape design. In this paper, a method analyze simultaneous inflow Mach number, incidence uncertainties was proposed. To make uncertainty modeling faster closer engineering practice, parametric mathematical model based on...

In order to advance the understanding of fundamental mechanisms axial skewed slot casing treatment and their effects on subsonic axial-flow compressor flow field, coupled unsteady through a rotor was simulated with state-of-the-art multiblock solver. The computational results were first compared available measured data, that showed numerical procedure calculates overall effect correctly. Then, numerically obtained fields interrogated identify physical mechanism responsible for improvement in...

Three-dimensional unsteady calculations were performed to explore the nature of tip clearance flow and its possible linking with spike stall inception. It was found that interaction broken-down leakage vortex formed another distinctive vortex, denoted as separation vortex. below rotor blade section propagated diagonally inward. This across passage from pressure side suction core filled low-energy fluid. The emergence during inception included breakdown formation movement

The aim of this research was to explore the mechanisms underlying effect self-circulating casing treatment with different circumferential coverage ratios on aerodynamic performance a transonic centrifugal compressor. A three-dimensional unsteady numerical simulation carried out Krain impeller. casings were set 36%, 54%, 72% and 90%, respectively. results showed that Stall Margin Improvement (SMI) increased increase in ratios. 90% ratio exhibited highest SMI at 20.22%. Internal flow field...

The impact of geometric deviation due to manufacturing on compressor performance is considerable in engineering practice. To investigate the blade thickness and flow loss at various rotational speeds, a three-dimensional steady numerical simulation Rotor 37 was conducted. quantification uncertainty accomplished using non-intrusive polynomial chaos method. viscous dissipation coefficient introduced analyze uncertain influence loss. Based type source, field divided into six regions, including...