The SAE MOBILUS platform will continue to be accessible and populated with high quality technical content during the coronavirus (COVID-19) pandemic. x

Your Selections

Scharf, Johannes
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Events

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Analysis of Drivability Influence on Tailpipe Emissions in Early Stages of a Vehicle Development Program by Means of Engine-in-the-Loop Test Benches

FEV Europe GmbH-Stefan Tegelkamp, Michael Görgen, Martin Nijs, Johannes Scharf
RWTH Aachen University-Christian Heusch, Daniel Guse, Frank Dorscheidt, Johannes Claßen, Timm Fahrbach, Stefan Pischinger
  • Technical Paper
  • 2020-01-0373
To be published on 2020-04-14 by SAE International in United States
Due to increasing environmental awareness, standards for pollutant and CO2 emissions are getting stricter in most markets around the world. In important markets such as Europe, also the emissions during real road driving, so called “Real Driving Emissions” (RDE), are now part of the type approval process for passenger cars. In addition to the proceeding hybridization and electrification of vehicles, the complexity and degrees of freedom of conventional powertrains with internal combustion engines (ICE) are also continuing to increase in order to comply with stricter exhaust emission standards. Besides the different requirements placed on vehicle emissions, the drivability capabilities of passenger vehicles desired by customers, are essentially important and vary between markets. As the interactions between different hardware and software parts of the powertrain strongly influence the drivability characteristics of a vehicle, a high degree of maturity of test vehicles is required to execute drivability calibration tasks with a reliable evidence. Hence, these calibration and evaluation tasks are generally conducted in late phases of the vehicle development process where the engines base calibration is already…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Relevance of Exhaust Aftertreatment System Degradation for EU7 Gasoline Engine Applications

FEV Europe GmbH-Michael Görgen, Jim Cox, Martin Nijs, Johannes Scharf
RWTH Aachen University-Stefan Sterlepper, Johannes Claßen, Stefan Pischinger
  • Technical Paper
  • 2020-01-0382
To be published on 2020-04-14 by SAE International in United States
Exhaust aftertreatment systems must function sufficiently over the full useful life of a vehicle. In Europe this is currently defined as 160.000 km. With the introduction of Euro 7 it is expected that the required mileage will be extended to 240.000 km. This will then be consistent with the US legislation.In order to quantify the emission impact of exhaust system degradation, an Euro 7 exhaust aftertreatment system is aged by different accelerated approaches: application of the Standard Bench Cycle, the ZDAKW cycle, a novel ash loading method and borderline aging. The results depict the impact of oil ash on the oxygen storage capacity. For tailpipe emissions, the maximum peak temperatures are the dominant aging factor. The cold start performance is effected by both, thermal degradation and ash accumulation.An evaluation of this emission increase requires appropriate benchmarks. For this purpose, an analysis of the emission impacts of ambient temperatures, driving modes and particulate filter regenerations follows. The comparison shows the severe impact of very low ambient conditions. Considering the high statistical relevance of catalyst degradation however,…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Objectified Evaluation and Classification of Passenger Vehicles Longitudinal Drivability Capabilities in Automated Load Change Drive Maneuvers at Engine-in-the-Loop Test Benches

FEV Europe GmbH-Stefan Tegelkamp, Martin Nijs, Johannes Scharf
RWTH Aachen University-Daniel Guse, Christian Heusch, Serge Klein, Timm Fahrbach, Jakob Andert, Stefan Pischinger
  • Technical Paper
  • 2020-01-0245
To be published on 2020-04-14 by SAE International in United States
The growing number of passenger car variants and derivatives in all global markets, their high order of software differentiability caused by regionally different legislative regulations, as well as pronounced market-specific customer expectations require a continuous optimization of the entire vehicle development process. Additionally, the continued increasingly stringent emission standards lead to considerable increases in powertrain hardware and control complexity. Also, efforts to achieve global market and brand specific multistep adjustable drivability characteristics as unique selling proposition, rapidly increase the scope for calibration and testing tasks during the development of the powertrain control units. The resulting extent of interdependencies between the drivability calibration and other development and calibration tasks require frontloading of development tasks. Usually, drivability calibration takes place towards the end of the vehicle development program as soon as a sufficient level of product maturity is achieved. Hence, for streamlining the entire development process, various powertrain engineering tasks have to be shifted from the overall vehicle level to component conception phases. In this context, highly dynamic “Hardware-in-the-Loop” (HiL) component test benches are the means of…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Analysis of the Emission Conversion Performance of Gasoline Particulate Filters Over Lifetime

Corning GmbH-Dominik Rose, Thorsten Boger
FEV Europe GmbH-Christof Schernus, Michael Görgen, Jim Cox, Martin Nijs, Johannes Scharf
Published 2019-09-09 by SAE International in United States
Gasoline particulate filters (GPF) recently entered the market, and are already regarded a state-of-the-art solution for gasoline exhaust aftertreatment systems to enable EU6d-TEMP fulfilment and beyond. Especially for coated GPF applications, the prognosis of the emission conversion performance over lifetime poses an ambitious challenge, which significantly influences future catalyst diagnosis calibrations. The paper presents key-findings for the different GPF application variants. In the first part, experimental GPF ash loading results are presented. Ash accumulates as thin wall layers and short plugs, but does not penetrate into the wall. However, it suppresses deep bed filtration of soot, initially decreasing the soot-loaded backpressure. For the emission calibration, the non-linear backpressure development complicates the soot load monitoring, eventually leading to compromises between high safety against soot overloading and a low number of active regenerations. In the second part, a relevant share of ash deposits inside three-way catalysts (TWC) is depicted. In an experiment, the oxygen storage capacity (OSC) of a three-way catalyst was significantly lowered by ash, while a coated GPF showed little effects. A subsequent OSC regeneration…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Objectified Drivability Evaluation and Classification of Passenger Vehicles in Automated Longitudinal Vehicle Drive Maneuvers with Engine Load Changes

FEV Europe GmbH-Stefan Tegelkamp, Christopher Schmidt, Henning Roehrich, Martin Nijs, Johannes Scharf
RWTH Aachen University-Daniel Guse, Christian Heusch, Stefan Pischinger
Published 2019-04-02 by SAE International in United States
To achieve global market and brand specific drivability characteristics as unique selling proposition for the increasing number of passenger car derivatives, an objectified evaluation approach for the drivability capabilities of the various cars is required. Thereto, it is necessary to evaluate the influence of different engine concepts in various complex and interlinked powertrain topologies during engine load change maneuvers based on physical criteria. Such an objectification approach enables frontloading of drivability related engineering tasks by the execution of drivability development and calibration work within vehicle subcomponent-specific closed-loop real-time co-simulation environments in early phases of a vehicle development program. So far, drivability functionalities could be developed and calibrated only towards the end of a vehicle development program, when test vehicles with a sufficient level of product maturity became available. The resulting compaction and parallelization of the calibration work to meet the emissions, on-board diagnostics as well as the drivability requirements drastically reduces development costs and time.This article presents an objectified drivability evaluation and classification approach for passenger cars, which is based on physical criteria, developed at…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Virtual Transmission Evaluation Using an Engine-in-the-Loop Test Facility

FEV Europe GmbH-Johannes Scharf, Martin Nijs, Ralf Wellers, Yi Zhang
RWTH Aachen University-Daniel Guse, Serge Klein, Jakob Andert, Stefan Pischinger
Published 2018-04-03 by SAE International in United States
This paper describes an approach to reduce development costs and time by frontloading of engineering tasks and even starting calibration tasks already in the early component conception phases of a vehicle development program. To realize this, the application of a consistent and parallel virtual development and calibration methodology is required. The interaction between vehicle subcomponents physically available and those only virtually available at that time, is achieved with the introduction of highly accurate real-time models on closed-loop co-simulation platforms (HiL-simulators) which provide the appropriate response of the hardware components.This paper presents results of a heterogeneous testing scenario containing a real internal combustion engine on a test facility and a purely virtual vehicle using two different automatic transmission calibration and hardware setups. The first constellation is based on an already validated vehicle model (A), including a physical dual-clutch transmission model (DCT), a semi-physical tire model and a vehicle dynamics model. With this standard configuration, the real-time model accuracy is initially illustrated by comparing the operating points distribution and the tailpipe emissions (diluted vs. undiluted) in “Worldwide…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Evaluation of the Potential of Water Injection for Gasoline Engines

SAE International Journal of Engines

FEV Europe GmbH-Matthias Thewes, Joerg Seibel, Andreas Balazs, Johannes Scharf
VKA, RWTH Aachen University-Fabian Hoppe
  • Journal Article
  • 2017-24-0149
Published 2017-09-04 by SAE International in United States
Gasoline engine powertrain development for 2025 and beyond is focusing on finding cost optimal solutions by balancing electrification and combustion engine efficiency measures. Besides Miller cycle application, cooled exhaust gas recirculation and variable compression ratio, the injection of water has recently gained increased attention as a promising technology for significant CO2 reduction. This paper gives deep insight into the fuel consumption reduction potential of direct water injection. Single cylinder investigations were performed in order to investigate the influence of water injection in the entire engine map. In addition, different engine configurations were tested to evaluate the influence of the altering compression ratios and Miller timings on the fuel consumption reduction potential with water injection. Based on the single cylinder investigations, drive cycle simulations covering a low, intermediate, and high load profiles were performed to evaluate the fuel consumption reduction potential as well as the corresponding water consumption under varying load demands for the different engine configurations. Furthermore, these simulations were used to optimize the water injection rate for the altering boundary conditions regarding the trade-off…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Sectoral Approach to Modelling Wall Heat Transfer in Exhaust Ports and Manifolds for Turbocharged Gasoline Engines

SAE International Journal of Materials and Manufacturing

FEV GmbH-Philipp Adomeit, Christof Schernus, Johannes Scharf, Tolga Uhlmann
RWTH Aachen University-Bjoern Franzke, Stefan Pischinger
  • Journal Article
  • 2016-01-0202
Published 2016-04-05 by SAE International in United States
A new approach is presented to modelling wall heat transfer in the exhaust port and manifold within 1D gas exchange simulation to ensure a precise calculation of thermal exhaust enthalpy. One of the principal characteristics of this approach is the partition of the exhaust process in a blow-down and a push-out phase. In addition to the split in two phases, the exhaust system is divided into several sections to consider changes in heat transfer characteristics downstream the exhaust valves. Principally, the convective heat transfer is described by the characteristic numbers of Nusselt, Reynolds and Prandtl. However, the phase individual correlation coefficients are derived from 3D CFD investigations of the flow in the exhaust system combined with Low-Re turbulence modelling. Furthermore, heat losses on the valve and the seat ring surfaces are considered by an empirical model approach.Since the comparison between measured and simulated exhaust temperature at turbine inlet serves as an evaluation criterion, a detailed 1D thermocouple model is implemented. Exothermic exhaust after-reactions are represented by a reduced reaction kinetics mechanism. The investigations were carried…
Annotation ability available