Effects of Pulsation Frequency and Pulse Shape on Turbine Performance
(English)Manuscript (preprint) (Other academic)
The current paper studies the pulsating flow in the exhaust manifold and turbine of a passenger car engine. The study focuses on three engine RPMs and two different pulse shapes, one normal shape and one shorter DEP like shape. By simulating different valve strategies one can investigate how to maximize the available exhaust flow energy to the turbine. The simulations have been performed with the Large Eddy Simulation (LES) method with boundary conditions received from GT-Power simulations. The study focuses on kinetic energy and turbine torque analysis of the incoming flow and of the flow in the turbine wheel region. It is found that the pulse shape is affecting the wheel torque significantly and that the kinetic energy entering the wheel region is different depending on which cylinder fired.
Fluid Mechanics and Acoustics
IdentifiersURN: urn:nbn:se:kth:diva-151398OAI: oai:DiVA.org:kth-151398DiVA: diva2:748458
QS 20142014-09-192014-09-192014-09-19Bibliographically approved