Effect of the Reynolds number and the basic design parameters on the isothermal flow field of low-swirl combustors

This study deals with isothermal low-swirling flows generated by axial swirlers and aims at providing a comprehensive insight of the flow field by considering the effect of the Reynolds number and some relevant design parameters of the swirler-combustion chamber assembly. The paper collects, rearranges, and compares velocity measurements reported in the open literature on combustors of similar geometry and swirl number. The literature data sets are expanded with original measurements performed by the authors on a laboratory combustor characterised by a high expansion ratio. Although the considered data sets are quite limited, the comparison between velocity measurements shows quite clear data trends and motivates additional systematic tests to be performed on different configurations of the same baseline design.