Wells turbine is very sensitive to changes in the tip clearance, and a reasonable modification of the tip clearance of the Wells turbine can help to improve its performance. In this paper, three kinds of Wells turbines with different tip clearances were studied by the computational fluid dynamics (CFD) technique. Under the condition of controlling the tip clearances, the performance of these three Wells turbines were investigated by comparing their output, efficient operating range, energy conversion efficiency, and the scope of application. The root causes of the differences in their performances were figured out by analyzing the flow fields and pressure fields. Results showed that the energy conversion efficiency of Wells turbines with expanding tip clearances were higher than the others, but they were more prone to stall. There existed a maximum output and wider operating range for Wells turbines with uniform tip clearance; compared to the front both, Wells turbines with shrinking tip clearance were non-protruding.
FAN Jing-run
,
WU Bi-jun
. Effect of Tip Clearance Shape on the Wells Turbine[J]. Advances in New and Renewable Energy, 2019
, 7(2)
: 123
-128
.
DOI: 10.3969/j.issn.2095-560X.2019.02.003
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