589 / 2019-01-19 20:03:18

Study on the aerodynamic performance of a cross-flow fan modified with tandem blade

cross flow fan tandem blade eccentric vortex noise

全体主题 > 数值模拟、建模与CFD

The internal flow of the cross-flow fan is very complicated. Now the main problem is that the cross-flow fan has high noise. So it is of great importance to study the method of reducing the noise on engineering. In this paper, the concept of aero engine’s tandem blade is introduced into the study of cross flow fan. Different tandem blade schemes were calculated by CFD. By setting a group of tandem blades at blade dorsal and blade basin and comparing with the standard case of the cross-flow fan ,we can analyze different cases of the cross-flow fan about the differences of aerodynamic performance. The results revealed that, compared with the standard case ,the position of the eccentricity vortex in the first case (1mm dislocation of the small blade in the direction of the blade dorsal) and the second case (1mm dislocation of the small blade in the direction of the blade basin) don’t have obvious change in the flow field. Therefore, it can be considered that there is almost no additional influence into the flow field after the introduce of the tandem blade .In terms of noise, the introduce of tandem blades plays an important role in noise reduction .If the impeller is taken as the noise source for analysis, the noise in the first case reduces about 3dB, and the second case remains unchanged. If the volute is taken as the noise source for analysis, the noise in the first case reduced about 10dB and the second case reduced about 2dB.If the whole part is taken as the noise source for analysis, the noise in the first case reduced about 2dB, and the second case remains unchanged .For each case, the noise generated by the impeller is greater than the noise generated by the volute and it is close to the noise generated by the whole part.