TY - CHAP A1 - Aslanjan, Jana A1 - Klauer, Christian A1 - Guenther, Vivien A1 - Mauß, Fabian T1 - Simulation of a three-way catalyst using a transient multi-channel model T2 - Digital Proceedings of the 8th European Combustion Meeting (ECM 2017), Dubrovnik, Croatia N2 - The conversion effects of a three-way catalyst (TWC) are simulated in previous works using single-channel approaches and detailed kinetic models. In addition to the single-channel model multiple representative catalyst channels are used in this work to take heat transfer between the channels into account. Furthermore, different inlet temperature distributions are considered and tested. An experimental four-stroke engine setup with emission outputs fed into a TWC is used to validate the model. Furthermore, the temperature progress is simulated to reflect the catalyst’s light off temperature. Heat conduction between the channels is modeled to provide proper heat dissipation during the catalytic process. A good agreement to the experimental data can be achieved with low computational cost. Y1 - 2017 UR - https://www.researchgate.net/profile/Jana_Aslanjan/publication/319136860_Simulation_of_a_three-way_catalyst_using_a_transient_multi-channel_model/links/59941a8caca272ec9087c553/Simulation-of-a-three-way-catalyst-using-a-transient-multi-channel-model.pdf SP - 570 EP - 574 CY - Dubrovnik ER - TY - GEN A1 - Aslanjan, Jana A1 - Klauer, Christian A1 - Günther, Vivien A1 - Mauß, Fabian T1 - Simulation of a three-way-catalyst using a transient multi-channel model N2 - The importance to reduce automotive exhaust gas emissions is constantly increasing. Not only the country-specific laws are getting more stringent also the global increase of automobiles is requiring a responsible handling of the issue. The three-way-catalytic converter (TWC) is one of the most common catalysts for the engine exhaust gas after treatment. The reduction of CO, NO and unburned hydrocarbons is fulfilled via oxidation of carbon monoxide and hydrocarbons, and reduction of nitrogen oxides. These conversion effects were simulated in previous works using single channel approaches [e.g. Fröjd/Mauss, SAE International 2011-01-1306] and detailed kinetic models [e.g Chatterjee et al., Faraday Discussions 119 (2001) 371-384 and Koop et al., Appl. Catal.B: Environmental 91 (2009), 47-58]. In this work multiple representative catalyst channels are used to take heat variations in between the catalyst into account. Each channel is split into a user given number of cells and each cell is treated like a perfectly stirred reactor (PSR). The simulation is validated against an experimental four-stroke engine setup with emission outputs fed into a TWC. Next to the emissions the transient temperature increase is simulated in order to model the catalyst light off temperature. The heat transfer is modelled by wall heat losses to provide a proper heat dissipation out of the catalyst. The simulation results show a good agreement to the experimental data with low computational cost. Y1 - 2017 UR - https://unitedscientificgroup.com/conferences/catalysis/2017/pdfs/CCE-2017_Proceedings.pdf N1 - CCE-2017 International Conference on Catalysis and Chemical Engineering Baltimore, USA, February 22 - 24, 2017 SP - S. 103 ER - TY - GEN A1 - Van Treek, Lisa A1 - Roth, Norbert A1 - Seidel, Lars A1 - Mauß, Fabian T1 - Laminar burning velocities of rich ethylene / air flames N2 - The laminar burning velocity SL of a given mixture of fuel and oxidizer is an important parameter to characterize premixed flames. SL is not only a fundamental parameter to calculate properties of turbulent flames, it is also an important target for the development of chemical kinetic mechanisms. Under fuel rich conditions it has relevance when simulating soot formation in burner stabilized flames. Many experiments on soot formation have been conducted in fuel-rich burner stabilized ethylene flames. Therefore an interest exists in experimental data for laminar burning velocity, in particular in fuel-rich ethylene flames. In the present work, ethylene / air flames were measured in the heat flux setup. Subsequently, the experimental data were compared against existing data and modelled using two kinetic models. KW - laminar burning velocity KW - ethylene / air flames KW - rich flames Y1 - 2017 UR - https://www.researchgate.net/publication/320802733_Laminar_burning_velocities_of_rich_ethylene_air_flames N1 - 3rd General Meeting and Workshop on Smart Energy Carriers in Industry – Prague, October 25 - 27, 2017 ER - TY - GEN A1 - Hoyermann, Karlheinz A1 - Mauß, Fabian A1 - Olzmann, Matthias A1 - Welz, Oliver A1 - Zeuch, Thomas T1 - Exploring the chemical kinetics of partially oxidized intermediates by combining experiments, theory, and kinetic modeling T2 - Physical Chemistry Chemical Physics N2 - Partially oxidized intermediates play a central role in combustion and atmospheric chemistry. In this perspective, we focus on the chemical kinetics of alkoxy radicals, peroxy radicals, and Criegee intermediates, which are key species in both combustion and atmospheric environments. These reactive intermediates feature a broad spectrum of chemical diversity. Their reactivity is central to our understanding of how volatile organic compounds are degraded in the atmosphere and converted into secondary organic aerosol. Moreover, they sensitively determine ignition timing in internal combustion engines. The intention of this perspective article is to provide the reader with information about the general mechanisms of reactions initiated by addition of atomic and molecular oxygen to alkyl radicals and ozone to alkenes. We will focus on critical branching points in the … KW - reaction kinetics KW - atmospheric chemistry KW - combustion chemistry Y1 - 2017 U6 - https://doi.org/10.1039/C7CP02759A SN - 1463-9076 SN - 1463-9084 VL - 19 IS - 28 SP - 18128 EP - 18146 ER - TY - GEN A1 - Weber, Kathrin A1 - Li, T. A1 - Løvås, Terese A1 - Perlman, Cathleen A1 - Seidel, Lars A1 - Mauß, Fabian T1 - Stochastic reactor modeling of biomass pyrolysis and gasification T2 - Journal of analytical and applied pyrolysis N2 - Abstract In this paper, a partially stirred stochastic reactor model is presented as an alternative for the modeling of biomass pyrolysis and gasification. Instead of solving transport equations in all spatial dimensions as in CFD simulations, the description of state variables and mixing processes is based on a probability density function, making this approach computationally efficient. The virtual stochastic particles, an ensemble of flow elements consisting of porous solid biomass particles and surrounding gas, mimic the turbulent exchange of heat and mass in practical systems without the computationally expensive resolution of spatial dimensions. Each stochastic particle includes solid phase, pore gas and bulk gas interaction. The reactor model is coupled with a chemical mechanism for both surface and gas phase reactions. A Monte Carlo algorithm with operator splitting … KW - Pyrolysis KW - gasification KW - Stochastic reactor modeling Y1 - 2017 U6 - https://doi.org/10.1016/j.jaap.2017.01.003 SN - 0165-2370 VL - 124 SP - 592 EP - 601 ER - TY - GEN A1 - Seidel, Lars A1 - Netzer, Corinna A1 - Hilbig, Martin A1 - Mauß, Fabian A1 - Klauer, Christian A1 - Pasternak, Michal A1 - Matrisciano, Andrea T1 - Systematic reduction of detailed chemical reaction mechanisms for engine applications T2 - Journal of Engineering for Gas Turbines and Power N2 - In this work, we apply a sequence of concepts for mechanism reduction on one reaction mechanism including novel quality control. We introduce a moment-based accuracy rating method for species profiles. The concept is used for a necessity-based mechanism reduction utilizing 0D reactors. Thereafter a stochastic reactor model for internal combustion engines is applied to control the quality of the reduced reaction mechanism during the expansion phase of the engine. This phase is sensitive on engine out emissions, and is often not considered in mechanism reduction work. The proposed process allows to compile highly reduced reaction schemes for computational fluid dynamics application for internal combustion engine simulations. It is demonstrated that the resulting reduced mechanisms predict combustion and emission formation in engines with accuracies comparable to the original detailed scheme. KW - Reaction Mechanism Reduction KW - Engine Modelling Y1 - 2017 U6 - https://doi.org/10.1115/1.4036093 SN - 1528-8919 SN - 0742-4795 VL - 139 IS - 9 SP - 091701-1 EP - 091701-9 ER - TY - GEN A1 - Nagy, Imre Gergely A1 - Matrisciano, Andrea A1 - Lehtiniemi, Harry A1 - Mauß, Fabian A1 - Schmid, Andreas T1 - Influence of nozzle eccentricity on spray structures in marine diesel sprays T2 - SAE technical papers N2 - Abstract: Large two-stroke marine Diesel engines have special injector geometries, which differ substantially from the configurations used in most other Diesel engine applications. One of the major differences is that injector orifices are distributed in a highly non-symmetric fashion affecting the spray characteristics. Earlier investigations demonstrated the dependency of the spray morphology on the location of the spray orifice and therefore on the resulting flow conditions at the nozzle tip. Thus, spray structure is directly influenced by the flow formation within the orifice. Following recent Large Eddy Simulation resolved spray primary breakup studies, the present paper focuses on spray secondary breakup odelling of asymmetric spray structures in Euler-Lagrangian framework based on previously obtained droplet distributions of primary breakup. Firstly, the derived droplet distributions were … KW - Marine Diesel KW - Spray Y1 - 2017 SN - 0148-7191 SN - 0096-5170 N1 - Event: 13th International Conference on Engines & Vehicles IS - 2017-24-0031 ER - TY - GEN A1 - Banyon, Colin A1 - Rodriguez Henriquez, Jose Juan A1 - Paterakis, George A1 - Malliotakis, Zisis A1 - Souflas, Konstantinos A1 - Keramiotis, Christos A1 - Vourliotakis, George A1 - Mauß, Fabian A1 - Curran, Henry J. A1 - Skevis, George A1 - Koutmos, Panagiotis A1 - Founti, Maria T1 - A comparative study of the effect of varied reaction environments on a swirl stabilized flame geometry via optical measurements T2 - Fuel : the science and technology of fuel and energy N2 - The present work is a part of a larger experimental campaign which examines the behaviour of various fuels on a swirl stabilized flame burner configuration. Overall, detailed speciation measurements and temperature measurements were combined with optical measurements. The work presented here concerns the part of the experimental campaign which deals with the optical characteristics of the examined flames. The work adds to the growing database of experimental measurements assessing engine-relevant reaction environments which shift from traditional ones in order to meet pollutant emission regulations and efficiency standards. Here, the oxidation of several commonly used fuel and fuel surrogates that are subjected to the addition of a bio-derived fuel additive (dimethyl ether) and emulated exhaust gas recirculation (EGR) is studied in a laboratory-scale swirl … KW - swirl burner KW - speciation measurements KW - temperature measurements Y1 - 2018 U6 - https://doi.org/10.1016/j.fuel.2017.09.105 SN - 0016-2361 VL - 216 SP - 826 EP - 834 ER - TY - GEN A1 - Medina Méndez, Juan Ali A1 - Schmidt, Heiko A1 - Mauß, Fabian A1 - Jozefik, Zoltan T1 - Constant volume n-Heptane autoignition using One-Dimensional Turbulence T2 - Combustion and Flame N2 - Abstract Constant volume premixed lean n-Heptane/air autoignition at high pressure is investigated using the One-Dimensional Turbulence (ODT) model. The configuration consists of a 1D fixed volume domain with a prescribed velocity spectrum and temperature fluctuations superimposed on an initial uniformly elevated scalar field. The sensitivity of the heat release rate and pressure evolution to the initial temperature distribution is studied by imposing different initial temperature fields while holding the mean, RMS and integral length scale of the field constant. Three detailed chemical mechanisms are employed for the prediction of autoignition and heat release rate. To mitigate the high computational cost associated with the calculation of the chemical source terms in the stiff complex mechanisms, an approach based on the Strang-Splitting method is presented. Finally, a … KW - One-Dimensional Turbulence KW - n-Heptane autoignition Y1 - 2018 U6 - https://doi.org/10.1016/j.combustflame.2017.12.015 SN - 0010-2180 VL - 190 SP - 388 EP - 401 ER - TY - CHAP A1 - Shrestha, Krishna Prasad A1 - Seidel, Lars A1 - Mauß, Fabian T1 - Kinetic study of methanol and ethanol oxidation in presence of NOx T2 - Workshop on Gas-phase reaction kinetics of biofuels oxygenated molecules KW - Gas-phase Reaction Y1 - 2018 UR - https://www.researchgate.net/publication/324731559 ER - TY - GEN A1 - Netzer, Corinna A1 - Franken, Tim A1 - Lehtiniemi, Harry A1 - Mauß, Fabian A1 - Seidel, Lars T1 - Numerical Analysis of the Impact of Water Injection on Combustion and Thermodynamics in a Gasoline Engine using Detailed Chemistry T2 - SAE technical papers Y1 - 2018 U6 - https://doi.org/10.4271/2018-01-0200 SN - 0148-7191 SN - 0096-5170 IS - 2018-01-0200 ER - TY - CHAP A1 - Netzer, Corinna A1 - Seidel, Lars A1 - Lehtiniemi, Harry A1 - Ravet, Frédéric A1 - Mauß, Fabian T1 - Impact of Formulation of Fuel Surrogates on Engine Knock Prediction T2 - International Multidimensional Engine Modeling User's Group Meeting at the SAE Congress, April 9th , 2018, Detroit, USA KW - Impact of Formulation of Fuel Surrogates Y1 - 2018 UR - http://www.erc.wisc.edu/imem/2018/Paper%234-Netzer%20et%20al.pdf ER - TY - GEN A1 - Aslanjan, Jana A1 - Klauer, Christian A1 - Günther, Vivien A1 - Mauß, Fabian T1 - Development of a Physical Parameter Optimizer for 1D Catalyst Modeling on the Example of a Transient Three-Way Catalyst Experiment, 37th International Symposium on Combustion 2018, Dublin N2 - The importance of catalytic after-treatment for automotive emissions is not neglectable concerning current environmental protection discussions. A reasonable and time efficient catalyst model can help to reduce the necessity of time consuming experimental investigations on physical parameters for catalytic converter construction. It can further support the preparation of necessary experimental setups to analyze physical and chemical phenomena in catalysts. Physical parameter and/or chemical kinetic optimizers can be an advanced tool to support computational models in terms of adjustment to an experiment. In this work a physical parameter optimizer is developed and validated against a transient three-way catalyst experiment. The modeling results are compared to the measured data in terms of temperature and emission conversion behavior and show a good agreement. KW - Three-Way Catalyst KW - 1D-Simulation KW - Emissions KW - After Treatment KW - Optimization Y1 - 2018 UR - https://www.researchgate.net/publication/328998399 ER -