Photo Credit: FVV | Ch. Yunck
First interim report of the internationally funded German-Japanese research project on the development of a post-oxidation model for 0D/1D engine simulation was presented // The project partners of the research and technology performers in Stuttgart (IVK) and Japan (Chiba, Meiji/Tokio) use the FVV 2019 Autumn Conference in Würzburg for further coordination of the research venture // Final results expected in spring 2021
After a delegation from the Institute for Internal Combustion Engines and Automotive Engineering (IVK) at the University of Stuttgart had travelled to Tokyo from 22 to 25 July 2019 to validate the first results of the joint post-oxidation research project with their Japanese colleagues from Chiba University and Meji University, the scientific directors of the participating research institutions, Professor Michael Bargende and Professor Yasuo Moriyoshi presented a first interim report at the FVV Autumn Conference in Würzburg on 19 September 2019.
Development of a post-oxidation model for 0D/1D engine simulation
The introduction of ever more dynamic drive cycles for passenger car type approvals, such as WLTP or Real Driving Emissions (RDE) measurements, demands an improvement of the transient engine behaviour while while simultaneously keeping the emissions to a minimum. The post-oxidation of rich combustion products in the exhaust manifold using scavenged air is a promising measure to achieve this goal.
Scavenging reduces the in-cylinder residual gas, thus reducing the combustion chamber temperature while the increased mass flow improves the dynamic behaviour of the exhaust gas turbocharger. However, the excess air impedes the effective operation of the three way catalyst. One way to solve this problem is to bind the excess air by products of rich combustion. This allows the dynamic behaviour of the turbocharger to be further improved by increasing the enthalpy of the exhaust gases. Additionally, the rich combustion decreases in-cylinder temperature even more and, thus, reduces knock tendency. A further benefit of post-oxidation is the possibility of reducing the heat-up time of the catalyst converter.
The aim of this project is to develop a post-oxidation model for 0D/1D engine simulation. To develop this model, a deeper understanding of the crucial mixing and oxidation process of scavenged air and rich combustion products is required. This project involves 3D CFD simulations including reaction kinetics in combination with test bench measurements. In order to reduce the 3D CFD computing time, a reduced reaction mechanism covering all important chemical processes of post-oxidation is being developed.
Based on test bed measurements, the post-oxidation model will additionally be expanded in order to be able to map processes within the turbine.
Finally, an RDE driving cycle will be simulated to demonstrate the potential of post-oxidation and to investigate critical manoeuvres in RDE.
01/01/2019 to 31/12/2020
BMWi/AiF/CORNET | 234 EN/1
FVV (Research Association for Internal Combustion Engines)
NEDO (Japanese New Energy and Industrial Technology Development Organisation)
AICE (Research Association of Automotive Internal Combustion)
Christine Burkhardt (EnginOS GmbH)
Yoshihiro Imaoka (Nissan Motor Co. Ltd)
Research and technology performers:
Prof. Dr.-Ing. Michael Bargende (IVK | University of Stuttgart)
Prof. Dr. Yasuo Moriyoshi (Chiba University)
Prof. Dr. Tetsuya Aizawa (Meiji University)
The aim of this innovative research project is to develop a post-oxidation model for 0D/1D engine simulation, which requires a deeper understanding of the critical mixing and oxidation process of scavenged air and rich combustion products. The research performers want to develop a mixture-optimised exhaust manifold geometry and evaluate it on the engine test bed.
The new post-oxidation model is required for the simulation of an RDE driving cycle (measurement of emissions in realworld operation) to improve transient engine behaviour while simultaneously minimising emissions. For example, critical acceleration manoeuvres can be investigated that can lead to the maximum catalyst temperature being exceeded.
While the test bed measurements are carried out by Chiba and Meiji University in Japan, IVK supervises the CFD simulations and the development of 0D/1D models. The project is scheduled to be completed by December 2020.
Caption (from left to right):
Prof. Dr. Tatsuya Kubayama (Chiba University), Kazuo Takeuchi (Toyota), Prof. Dr.-Ing. Michael Bargende (IVK | University of Stuttgart), Christine Burkhardt (EnginOS), Prof. Dr. Yasuo Moriyoshi (Chiba University)
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