Mathematical Simulating of the Flow in the Fan Impeller with Meridional Acceleration

Abstract

The article considers a comparison of the methods for simulating the flow in the fan impeller with the meridional acceleration of the flow. The aim of this work is to compare the results of flow simulation obtained using the method of calculating the flow along axisymmetric current surfaces with variable thickness in relative motion with the solution obtained by the CFD method. The discrepancy between the results of determining the pressure for the test problem --- the flow in an elementary blade row is not exceeded 2 % with a continuous flow. The resulting distribution of velocity along the contour of the blade makes it possible to proceed to the calculation of the boundary layer on its surface and to take into account the profile losses in the rotor, as well as to clarify the location of the trailing points on the profile. The presented work shows the possibility of using the method of calculating the flow along axisymmetric current surfaces with variable thickness for profiling axial fans with meridional flow acceleration. The rotor was profiled using the method described in the article and a CFD calculation was performed, which confirmed the theoretical head coefficient Ht = 0.68 laid down during profiling at a given flow rate ca1 = 0.5, the total efficiency in the rotor was η∗f.i = 0.93