Inlet Gap Influence on Low-Frequency Flow Unsteadiness in a Centrifugal Fan
Artikel i vetenskaplig tidskrift, 2022

In this study, unsteady low-frequency characteristics in a voluteless low-speed centrifugal fan operating at a high mass flow rate are studied with improved delayed detached eddy simulation (IDDES). This study is motivated by a recent finding that the non-uniformly distributed pressure inside this type of fan could be alleviated by improving the gap geometry. The present simulation results show that the velocity magnitudes of the gap have distinct low and high regions. Intensive turbulent structures are developed in the low-velocity regions and are swept downstream along the intersection between the blade and shroud, on the pressure side of the blade. Eventually, the turbulence gives rise to a high-pressure region near the blade’s trailing edge. This unsteady flow behavior revolves around the fan rotation axis. Additionally, its period is 5% of the fan rotation speed, based on the analysis of the time history of the gap velocity magnitudes and the evolution of the high-pressure region. The same frequency of high pressure was also found in previous experimental measurements. To the authors’ knowledge, this is the first time that the trigger of the gap turbulence, i.e., the unsteady local low velocity, has been determined.

voluteless centrifugal fan

IDDES

gap turbulence

low-frequency unsteadiness

Författare

Martin Ottersten

Chalmers, Mekanik och maritima vetenskaper, Strömningslära

Huadong Yao

Chalmers, Mekanik och maritima vetenskaper, Strömningslära

Lars Davidson

Chalmers, Mekanik och maritima vetenskaper, Strömningslära

Aerospace

22264310 (eISSN)

Vol. 9 12 846

Minskning av ljud från centrifugalfläktar

Swegon, 2017-03-01 -- 2022-02-28.

Ämneskategorier

Maskinteknik

Rymd- och flygteknik

Energiteknik

Strömningsmekanik och akustik

Fusion, plasma och rymdfysik

Styrkeområden

Transport

Energi

Infrastruktur

C3SE (Chalmers Centre for Computational Science and Engineering)

DOI

10.3390/aerospace9120846

Mer information

Senast uppdaterat

2023-01-09