The Influence of Blade Tip Loading Distribution on the Performance of a High Loading Centrifugal Impeller

2018 2nd International Conference on Advanced Technologies in Design, Mechanical and Aeronautical Engineering

工业技术;机械制造;航空航天工程

Wang, Yilin^1 ; Li, Zefeng^1 ; Jin, Donghai^1,2 ; Gui, Xingmin^1,2

School of Energy and Power Engineering, Beihang University, Beijing, China^1

Collaborative Innovation Center for Advanced Aero-engine, Beijing, China^2

关键词: Adverse effect;    Centrifugal impeller;    Design flow rate;    Different distributions;    Inverse design methods;    Loading distribution;    Stable operation;    Total pressure ratio;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/408/1/012028/pdf
DOI  :  10.1088/1757-899X/408/1/012028

来源: IOP

【 摘 要 】

It has been proved that different blade loading distributions between tip and hub has a significant effect on centrifugal impeller performance, but the effect of loading difference at different location along the stream has not been fully understood. In this paper, several blades were modelled by a three-dimensional inverse design method, in which the impellers are defined by the blade loading distribution at its tip and hub and the flows are computed numerically by a commercial CFD code. Firstly, two impellers were modelled using the same distribution at the hub but giving different distributions at tip. The results show that the impeller with a smoother tip loading distribution performs better. At design flow rate, the total pressure ratio is found to be 1.8% higher and the efficiency rises 1.36% as well. Then a further research about the effect of increasing tip load at different parts along the flow path was carried out. Further analysis indicates that adding the load at the fore part of tip could increase the efficiency at design flow rate and brings more uniform impeller exit flow. However, the surge margin was narrowed by such change. Besides, adding the v ur at the aft part of tip will promote the pressure ratio, with no adverse effect on the stable operation range.