Effect of Staggered Splitters on the Flow Characteristics in a Centrifugal Fan – A Numerical Study

In this paper, a CFD approach is used to analyse the through flow in a centrifugal fan fitted with backward swept impeller and a diffuser ring around it. Splitter blade technique is a common procedure to suppress the recirculation within the diffusing blade passages. In the present analysis, several configurations of splitter geometry have been tried for better flow stabilization, with splitters provided on the impeller side and the diffuser side as well. It is found from the analysis that the splitter geometries staggered to the left in the impeller blade passage corresponding to its exit location in combination with the diffuser splitters staggered to the inlet right of the diffuser passage provide relatively lower total pressure loss when compared to the base model without splitters. A different splitter geometry configuration with the impeller splitter kept at the right of impeller inlet in combination with the diffuser splitters placed to the left of the diffuser exit flow passage also showed a marginal improvement in the performance. However, the performance gets deteriorated for splitters tried at the right of impeller blade passage at its exit in combination with a diffuser splitter kept at its inlet left when compared to the base model.