TY - GEN
T1 - Assessment of unsteady behavior in turbocharger turbines
AU - Costall, Aaron
AU - Szymko, Shinri
AU - Martinez-Botas, Ricardo F.
AU - Filsinger, Dietmar
AU - Ninkovic, Dobrivoje
PY - 2006
Y1 - 2006
N2 - The flow in turbocharger turbines is highly unsteady in nature as it responds to the exhaust manifold of an internal combustion engine. This paper investigates the significance of unsteadiness by examining first its relevance to real engine situations and then its effect on turbocharger turbine operation. The engine simulations carried out show the relevance of the Strouhal number effect for real turbocharger applications, which has been demonstrated experimentally on a turbine stage test stand. Therefore, for realistic multiple-cylinder-engine configurations with different exhaust gas pipe lengths and firing frequencies the importance of the actual unsteady behavior needs careful assessment. The effect upon the turbine itself is examined by modeling the laboratory arrangement to replicate the test stand configuration and operation using a one-dimensional wave action code. The ID model is validated against experimental results obtained using a new permanent magnet eddy-current dynamometer for a mixed flow turbine suitable for a medium-sized automotive application covering an equivalent speed range of 50-100%, U2/Cis of 0.3-1.1 and a pulse frequency of 20-80 Hz. The turbine model has been refined using unsteady experimental data and so enables the capture of unsteady effects in engine design codes. The beneficial effect of the ability of this model to predict turbine mass flow is discussed.
AB - The flow in turbocharger turbines is highly unsteady in nature as it responds to the exhaust manifold of an internal combustion engine. This paper investigates the significance of unsteadiness by examining first its relevance to real engine situations and then its effect on turbocharger turbine operation. The engine simulations carried out show the relevance of the Strouhal number effect for real turbocharger applications, which has been demonstrated experimentally on a turbine stage test stand. Therefore, for realistic multiple-cylinder-engine configurations with different exhaust gas pipe lengths and firing frequencies the importance of the actual unsteady behavior needs careful assessment. The effect upon the turbine itself is examined by modeling the laboratory arrangement to replicate the test stand configuration and operation using a one-dimensional wave action code. The ID model is validated against experimental results obtained using a new permanent magnet eddy-current dynamometer for a mixed flow turbine suitable for a medium-sized automotive application covering an equivalent speed range of 50-100%, U2/Cis of 0.3-1.1 and a pulse frequency of 20-80 Hz. The turbine model has been refined using unsteady experimental data and so enables the capture of unsteady effects in engine design codes. The beneficial effect of the ability of this model to predict turbine mass flow is discussed.
UR - http://www.scopus.com/inward/record.url?scp=33750858711&partnerID=8YFLogxK
U2 - 10.1115/GT2006-90348
DO - 10.1115/GT2006-90348
M3 - Chapter in a published conference proceeding
AN - SCOPUS:33750858711
SN - 079184241X
SN - 9780791842416
T3 - Proceedings of the ASME Turbo Expo
SP - 1023
EP - 1038
BT - Proceedings of the ASME Turbo Expo 2006 - Power for Land, Sea, and Air
T2 - 2006 ASME 51st Turbo Expo
Y2 - 6 May 2006 through 11 May 2006
ER -