Effects of Pulsating Flow on Mass Flow Balance and Surge Margin in Parallel Turbocharged Engines
2015 (English)In: Proceedings of the 56th Conference on Simulation and Modelling (SIMS 56), October, 7-9, 2015, Linköping University, Sweden, Linköping: Linköping University Electronic Press, 2015, Vol. 119, 15-20 p.Conference paper (Refereed)
The paper extends a mean value model of a parallel turbocharged internal combustion engine with a crank angle resolved cylinder model. The result is a 0D engine model that includes the pulsating flow from the intake and exhaust valves. The model captures variations in turbo speed and pressure, and therefore variations in the compressor operating point, during an engine cycle. The model is used to study the effect of the pulsating flow on mass flow balance and surge margin in parallel turbocharged engines, where two compressors are connected to a common intake manifold. This configuration is harder to control compared to single turbocharged systems, since the compressors interact and can work against each other, resulting in co-surge. Even with equal average compressor speed and flow, the engine pulsations introduce an oscillation in the turbo speeds and mass flow over the engine cycle. This simulation study use the developed model to investigates how the engine pulsations effect the in cycle variation in compressor operating point and the sensitivity to co-surge. It also shows how a short circuit pipe between the two exhaust manifolds could increase surge margin at the expense of less available turbine energy.
Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2015. Vol. 119, 15-20 p.
Linköping Electronic Conference Proceedings, ISSN 1650-3686 (print), 1650-3740 (online) ; 119
Engine modeling; Engine simulation; Compressor surge; Turbocharging
Vehicle Engineering Fluid Mechanics and Acoustics Applied Mechanics
IdentifiersURN: urn:nbn:se:liu:diva-129822DOI: 10.3384/ecp1511915ISBN: 9789176859001OAI: oai:DiVA.org:liu-129822DiVA: diva2:944132
The 56th Conference on Simulation and Modelling (SIMS 56), October, 7-9, 2015, Linköping University, Sweden