Influence of tip clearance on flow behavior and noise generation of centrifugal compressors in near-surge conditions

CFD has become an essential tool for researchers to analyze centrifugal compressors. Tip leakage flow is usually considered one of the main mechanisms that dictate compressor flow field and stability. However, it is a common practice to rely on CAD tip clearance, even though the gap between blades a...

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Detalhes bibliográficos
Autores: Galindo, José|||0000-0001-6068-182X, Tiseira, Andrés-Omar|||0000-0001-9472-2386, Navarro, Roberto|||0000-0003-2587-4954, López Hidalgo, Miguel Andrés
Formato: artículo
Fecha de publicación:2015
País:España
Recursos:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/66078
Acesso em linha:https://riunet.upv.es/handle/10251/66078
Access Level:acceso abierto
Palavra-chave:CFD simulation
Turbocharger
Shaft motion
Aeroacoustics
DES
URANS
INGENIERIA AEROESPACIAL
MAQUINAS Y MOTORES TERMICOS
Descrição
Resumo:CFD has become an essential tool for researchers to analyze centrifugal compressors. Tip leakage flow is usually considered one of the main mechanisms that dictate compressor flow field and stability. However, it is a common practice to rely on CAD tip clearance, even though the gap between blades and shroud changes when compressor is running. In this paper, sensitivity of centrifugal compressor flow field and noise prediction to tip clearance ratio is investigated. 3D CFD simulations are performed with three different tip clearance ratios in accordance to expected operating values, extracted from shaft motion measurements and FEM predictions of temperature and rotational deformation. Near-surge operating conditions are simulated with URANS and DES. DES shows superior performance for acoustic predictions. Cases with reduced tip clearance present higher pressure ratio and isentropic efficiency, but no significant changes in compressor acoustic signature are found when varying clearance. In this working point, tip clearance is immersed in a region of strongly swirling backflow. Therefore, tip leakage cannot establish any coherent noise source mechanism.