The effect of tip winglet on the aerodynamic performance of compressor cascade are mainly determined by the location of the tip winglet, the tip winglet geometry, the size of tip clearance, and the aerodynamic parameters of the cascade. In this paper, an extensive numerical study which includes three aspects has been carried out to investigate the effects of these influencing factors in a highly-loaded compressor cascade in order to give the guidance for the application of tip winglet to control the tip leakage in modern highly-loaded compressor. Firstly, the numerical method is validated by comparing the numerical results with available measured data. Results show that the numerical procedure is valid and accurate. Then, the cascade flow fields are interrogate to identify the physical mechanism of how suction-side winglet improve the cascade flow behavior. It is found that a significant tip leakage mass flow rate and aerodynamic loss reduction is possible by using proper tip winglet located near the suction side corner of the blade tip. Finally, an optimum width of the suction-side tip winglet is obtained by comparing the compressor performance with different clearances and incidences. The use of the suction-side winglet can reduce the pressure difference between the pressure and the suction sides of the blade and tip leakage velocity ratio. And the winglet also can compact the tip leakage vortex structure, which is benefit to decrease the loss of the tip secondary flow mixing with the primary flow.

The adverse impacts of non-uniform inlet flow have been the focus for several decades with the increase of the operating range of engines. A deep understanding of the flow mechanism of distortion passing through a compressor is needed urgently and the improvement of the compressor performance becomes more and more important. In this paper, a non-axisymmetric stator is presented with significant non-axisymmetric characteristics in a transonic compressor to investigate compressor performance and flow field effects. A time-dependent three-dimensional Reynolds-averaged Navier-Stokes equation composed in ‘Fluent Software Pack’ is validated and used to perform the simulations. The flow fields with distorted inlet are obtained and the effects of original stator and non-axisymmetric stator in a transonic compressor are compared. The results are discussed in terms of the effects of non-axisymmetric stator on compressor performance, blockage of flow passage, rotor and stator. The results show that the non-axisymmetric stator influences not only the stator flow field but also the rotor flow field, so the efficiency and total pressure ratio are improved correspondingly.

Inlet total pressure distortion has great effects on the performance and stability of compressors. The Non-uniform flow influences the flow field of rotor tip and stator hub more significantly. If stall occurs, it often begins in one or both of these two regions. Which region is more sensitive to the nonuniform flow and how the mechanism of distorted flow influences the compressor flow field are topics of great importance and should be studied carefully. In this paper, the exploration of how the inlet total pressure distortion influences the flow field of rotor and stator end walls will base on the study of one-stage supersonic compressor with one rotor and one stator. Two aspects of the results will be analyzed in detail. The first aspect is about the dynamic response of shock wave to the inlet parameters in rotor casing area, the variation of shock wave intensity and structure with inlet flow parameters, and the mechanism of shock motion. The process of flow parameters variation in rotor cycle can be divided into four stages. The second aspect is about the analysis on the flow parameters near end walls and development of corner separation in stator. The study indicates that corner separation is induced by the distorted flow near stator hub and casing. Flow structures in each passage are different due to the different positions of distorted regions. The relationship between intensity and range of corner separation, and the change of inlet velocity angle and flow capacity, will be discussed in detail.

The surface wave generated by flow around a ship hull moving near free surface of water is simulated numerically in this study. The three-dimensional implicit finite volume method (FVM) is applied to solve Reynolds averaged Navier-Stokes (RANS) equation. The realizable k-ε turbulence model has been implemented to capture turbulent flow around the ship hull in the free surface zone. The volume of fluid (VOF) method coupled with the Stokes wave theory has been used to determine the free surface effect of water. By using is a six degrees of freedom model, the ship hull's movement is numerically solved with the Stokes wave together. Under the action of Stokes waves on the sea, the interface between the air and water waves at the same regular pattern and so does the pressure and the vertical velocity. The ship hull moves in the same way as the wave. The amplitude of the ship hull's heave is less than the wave height because of the viscosity damping. This method could provide an important reference for the study of ships' movement, wave and hydrodynamics.

The parachute inflation process is a typical time-varying, non-linear and fluid-structure coupling problem, especially inairdrop condition. For its complexity, numerical model of the inflation process is a big challenge, and most of the modelsestablished before still have room for improvement. There were two common problems that the first one was ignoranceof inertia force of canopy and line, and the second was that took stretch speed as the initial airdrop speed in modelling.Thus, a modified finite element model for canopy inflation process based on ALE (Arbitrary Lagrange Euler) method wasestablished that the inertia force of canopy and line was taken into consideration and the initial airdrop speed wasestimated and adjusted. The opening load in finite mass situation during deployment-inflation process of C-9 typeparachute was calculated. The result was compared to experimental data and calculated data of unmodified models. Itwas indicated that the opening load and peak time of modified model was the closest to experiment and the snatch loadwas also calculated and confirmed, so that the correctness and rationality of the model was verified. Then the factorinfluence of inertia force and initial airdrop speed was analysed, which provided a reference for parachute numericalmodelling.