Investigation On Influence Of Tip Clearance On Axial Compressor Performance With Uncertainty Quantification And POD Method

Tip clearance is one of the most important factors that affect the performance of a transonic axial compressor.Due to manufacturing errors,installation,long time running and other causes,the height of running tip clearance will change randomly,thus influencing the aerodynamic performance of a compressor.The uncertainty quantification of compressor performance and tip flow field is of great significance,in addition,POD analysis of tip leakage vortex under different tip clearances is also performed.The research object of this paper is NASA Rotor36,by comparing the numerical simulation results with experiments,the three-dimensional model and numerical simulation method can be proved to be true.NIPC method is implemented through programming,five classic test functions are selected to verify its accuracy and efficiency.Then the numerical simulation of Rotor36 under different tip clearances is performed,after obtaining the numerical results under different tip clearances,the uncertainty analysis of the numerical results is conducted to quantify the influence of tip clearance uncertainty on aerodynamic performance and tip flow field.Finally,the steady and unsteady computation under different tip clearances can be performed to analyze the structure and trajectory of tip leakage vortex,the dominant frequency of tip flow field and the trajectory of tip leakage vortex can be obtained by frequency analysis.In addition,by comparing POD modal and flow field under different tip clearances with POD method,the differences of percentage of dominant modal can be compared to analyze different mechanism under different condition.By combining all these results,we can further explore flow mechanism of flow field under different tip clearances.