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The Influence of Fuel Composition and Renewable Fuel Components on the Emissions of a GDI Engine

Porsche AG-Hans-Peter Deeg, Dietmar Schwarzenthal
Technical Univ of Braunschweig-Michael Albrecht, Peter Eilts
  • Technical Paper
  • 2020-37-0025
To be published on 2020-06-23 by SAE International in United States
Investigations were performed, in which the emission behavior of renewable and conventional fuels of different composition and renewable fuel components was observed. The influence on the emissions of the start of injection at different load points was investigated. This shows how much wall and valve wetting affects the mixture formation of the different fuels. Further, the air fuel ratio in an operating point for catalyst heating, with medium engine temperatures, was varied. The latter shows the ability of evaporation of the fuels at engine warm-up conditions and sub-stochiometric λ-Values. The studied fuels were four fuel mixtures of significantly different composition of which three were compliant with the European fuel standard EN 228. A RON 98 in-field fuel, a Euro 6 reference fuel, an Anti-Spark-Fouling (ASF) fuel (designed for minimum soot production) and a potentially completely renewable and CO2-neural fuel, which is designed by Dr. Ing. h.c. F. Porsche AG, named POSYN (POrsche SYNthetic fuel) were chosen. Additionally, the fuel components Ethanol as classic biofuel, Isopropanol, Isobutanol and methyl tert-butyl ether (MTBE), which were chosen by…
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How Should Innovative Combustion Engines be Developed, Operated and Built in Order to Turn From Climate Sinners Into Climate Savers?

Hamburg University of Applied Sciences-Victor Gheorghiu
  • Technical Paper
  • 2020-37-0009
To be published on 2020-06-23 by SAE International in United States
KEYWORDS – Strict Atkinson Cycle implementation, Extended Expansion Cycle, VCR, Enhanced Thermal Conversion Efficiency, High Pressure Turbocharging, Hydrogen DI, stoichiometric mixture, new load control ABSTRACT The Ultra-Downsizing is introduced as an even higher stage of downsizing of ICE. Ultra-downsizing will be implemented here by means of real Atkinson cycles using an asymmetrical crank mechanisms with continuous VCR capabilities, combined with two-stage high-pressure turbocharging and very intensive intercooling. This will allow an increase of ICE performance while keeping the thermal and mechanical strain strength of engine components within the current usual limits. Research Objective The principal purpose of this investigation is to analyze and evaluate a strict implementations of Atkinson cycles on Internal Combustion Engines (ICE) by means of the VCSR asymmetrical crank mechanisms (VCSR means Variable Compression and Strokes Ratios) for DI-Hydrogen-fueled (or with H2-CNG blends) case. The VCSR will be presented in two constructive variants. The mechanical loads as torque and forces within the VCSR crank mechanism will be presented and analyzed in some engine operation points. Methodology A small size SI NA MPI…
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On Maximizing Argon Engines' Performance via Subzero Intake Temperatures in HCCI Mode at High Compression Ratios

King Abdullah University of Science & Technology-Ali Elkhazraji, Abdulrahman Mohammed, Sufyan Jan, Jean-Baptiste Masurier, Robert Dibble, Bengt Johansson
  • Technical Paper
  • 2020-01-1133
To be published on 2020-04-14 by SAE International in United States
The improvement of the indicated thermal efficiency of an argon power cycle (replacing nitrogen with argon in the combustion reaction) is investigated in a CFR engine at high compression ratios in homogeneous charge compression ignition (HCCI) mode. The study combines the two effects that can increase the thermodynamic efficiency as predicted by the ideal Otto cycle: high specific heat ratio (provided by argon), and high compression ratios. However, since argon has relatively low heat capacity (at constant volume), it results in high in-cylinder temperatures, which in turn, leads to the occurrence of knock. Knock limits the feasible range of compression ratios and further increasing the compression ratio can cause serious damage to the engine due to the high pressure rise rate caused by advancing the combustion phasing. The technique proposed in this study in order to avoid intense knock of an argon cycle at high compression ratios is to cool the intake charge to subzero temperatures which leads to lower in-cylinder temperatures and hence, less possibility of having knock. The main variable in this study…
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Isobaric Combustion at a Low Compression Ratio

King Abdullah University of Science & Technology-Aibolat Dyuisenakhmetov, Harsh Goyal, Moez Ben Houidi, Rafig Babayev, Bengt Johansson
Saudi Aramco-Jihad Badra
  • Technical Paper
  • 2020-01-0797
To be published on 2020-04-14 by SAE International in United States
In a previous study, it was shown that isobaric combustion cycle, achieved by multiple injection strategy, is more favorable than conventional diesel cycle for the double compression expansion engine (DCEE) concept. In spite of lower effective expansion ratio, the indicated efficiencies of isobaric cycles were approximately equal to those of a conventional diesel cycle. Isobaric cycles had lower heat transfer losses and higher exhaust losses which are advantageous for DCEE since additional exhaust energy can be converted into useful work in the expander. In this study, the performance of low-pressure isobaric combustion (IsoL) and high-pressure isobaric combustion (IsoH) in terms of gross indicated efficiency, energy flow distribution and engine-out emissions is compared to the conventional diesel combustion (CDC) but at a relatively lower compression ratio of 11.5. The experiments are conducted in a Volvo D13C500 single-cylinder heavy-duty engine using standard EU diesel fuel. The current study consists of two sets of experiments. In the first set, the effect of exhaust gas recirculation (EGR) is studied at different combustion modes using the same air-fuel ratio obtained…
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Experimental and Numerical Assessment of Active Pre-chamber Ignition in Heavy Duty Natural Gas Stationary Engine

Istituto Motori CNR-Gessica Onofrio, Carlo Beatrice
Lund University-Changle Li, Pablo Garcia Valladolid, Per Tunestal
  • Technical Paper
  • 2020-01-0819
To be published on 2020-04-14 by SAE International in United States
Gas engines (fuelled with CNG, LNG or Biogas) for generation of power and heat are, to this date, taking up larger shares of the market with respect to diesel engines. In order to meet the limit imposed by the TA-Luft regulations on stationary engines, lean combustion represents a viable solution for achieving lower emissions as well as efficiency levels comparable with diesel engines. Leaner mixtures however affect the combustion stability as the flame propagation velocity and consequently heat release rate are slowed down. As a strategy to deliver higher ignition energy, an active pre-chamber may be used. This work focuses on assessing the performance of a pre-chamber combustion configuration in a stationary heavy-duty engine for power generation, operating at different loads, air-to-fuel ratios and spark timings. The engine was originally a 6-cylinder compression ignition engine which is here employed as a single cylinder engine and then suitably modified to host the pre-chamber (with its natural gas injection system and spark plug) with a new bowl piston to decrease compression ratio. A 0D model is built…
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Design and Simulation of a Multi Fuel Gas Mixture System of a Rotary Engine

University of Applied Sciences Zwickau-Tobias Dost, Joern Getzlaff
  • Technical Paper
  • 2020-01-0548
To be published on 2020-04-14 by SAE International in United States
The paper first includes the main objective and boundary conditions for design and simulation of a multi fuel gas mixture system of a rotary engine. New regenerative fuels are more and more important for use in automotive propulsion and stationary applications of combustion engines. Due the special design and operation of rotary engines there are opportunities for running these engines in future electric and hybrid applications with new designed liquids and gaseous fuels based on regenerative energy sources. The focus is on basic research and analyses of main physical and thermodynamic properties of separate lean burn gases (lower calorific value, mixed calorific value, AFR) and their effects on fuel mixing and combustion behavior. The work is focused on the development of simulation models capable to simulate the entire engine process and to map all factors influencing mixture formation and combustion of unconventional gaseous fuels. Moreover, analytical methods and modellation of the power estimation and fuel mixing are compared with 1d simulations of the fuel mixing and rotary engine thermodynamic performance. Analytical modells and calculations estimate…
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Optimization of Diesel Engine and After-treatment Systems for a Series Hybrid Forklift Application

IAV Automotive Engineering Inc.-Yinyan Huang, Thaddaeus Delebinski
IAV GmbH-Reza Rezaei, Rico Möllmann
  • Technical Paper
  • 2020-01-0658
To be published on 2020-04-14 by SAE International in United States
This paper investigates an optimal design of a diesel engine and after-treatment systems for a series hybrid electric forklift application. A holistic modeling approach is developed in GT-Suite® to establish a model-based hardware definition for a diesel engine and an after-treatment system to accurately predict engine performance and emissions. The used engine model is validated with the experimental data. The engine design parameters including compression ratio, boost level, air-fuel ratio (AFR), injection timing, and injection pressure are optimized at a single operating point for the series hybrid electric vehicle, together with the performance of the after-treatment components. The engine and after-treatment models are then coupled with a series hybrid electric powertrain to evaluate the performance of the forklift in the standard VDI 2198 drive cycle. In addition, the thermal management strategies like retarding injection timing and late post-injection of fuel during cold start are analyzed in this work. The results show the reduction of tailpipe- NOx emission is possible by properly retarding the injection timing without a significant effect on unburned hydrocarbon emissions.The designed series…
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A Novel Design of Engine Misfire Detection System Suitable for Small Capacity S.I. Engine for Two Wheeled Vehicle

TVS Motor Co., Ltd.-Monika Jayprakash Bagade, Himadri Bhushan Das, Arjun Raveendranath Sr, S Jabez Dhinagar
  • Technical Paper
  • 2020-01-0267
To be published on 2020-04-14 by SAE International in United States
As per the OBD II regulations, it is essential to detect and monitor the misfire event in an I.C. engine. Misfiring of an I.C. engine affects the quality of combustion and degrades the performance of catalyst convertor which can lead to an increase of emissions. Misfire event can be categorized as partial or complete, based on amount of combustion occurred during that particular engine cycle. Most of the production engine for non-two wheeler vehicle identifies misfire by monitoring angular acceleration of the engine crank-shaft. However, single cylinder engine with lower capacity (less than 300 cubic centimeter) provides challenges to identify misfire due to low mechanical inertia of the I.C. engine using the same approach. The problem of misfire identification for this category of I.C. engine turn out to be more challenging due to presence of various load disturbances on the powertrain. Ion current sensing is one of the alternate method to detect misfire, which received good attention during the last decade of the previous century. When the air-fuel mixture ignites inside the I.C. engine cylinder,…
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Evaluation of Trajectory Based Combustion Control for Electrical Free Piston Engine

University of Minnesota-Minal Nahin, Abhinav Tripathi, Zongxuan Sun
  • Technical Paper
  • 2020-01-1149
To be published on 2020-04-14 by SAE International in United States
Previously, the authors have proposed a novel strategy called trajectory based combustion control for the free piston engine (FPE) where the shape of the piston trajectory between top and bottom dead centers is used as a control input to modulate the chemical kinetics of the fuel-air mixture inside the combustion chamber. It has been shown that in case of a hydraulic free piston engine (HFPE), using active motion control, the piston inside the combustion chamber can be forced to track any desired trajectory, despite the absence of a crankshaft, providing reliable starting and stable operation. This allows the use of optimized piston trajectory for every operating point which minimizes fuel consumption and emissions. In this work, this concept is extended to an electrical free piston engine (EFPE) as a modular power source. A dynamic model of a linear electrical free piston engine unit has been developed which consists of a single phase linear generator driven by a single cylinder engine. The linear generator unit not only provides the required electromagnetic force to ensure precise trajectory…
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Real-world Emission Analysis Methods Using Sensor-based Emission Measurement System

Ibaraki University-Kotaro Tanaka
NGK Spark Plug Co., Ltd.-Takeshi Tange
  • Technical Paper
  • 2020-01-0381
To be published on 2020-04-14 by SAE International in United States
Every year, due to exhaust gas regulations that are getting stricter, the average air pollution is going to be solved, but the local roadside pollution is still pressing issue. In order to solve this local roadside pollution problem, it is necessary to evaluate and/or predict “where” and “how much” pollutants such as NOx are emitted. In recent years, Real Driving Emission regulations using PEMS (Portable Emission Measurement System) have been introduced mainly in Europe. However, PEMS has a configuration close to 100 kg, and its weight affects the driving conditions of vehicles running on actual roads. In this study, we focused on the analysis of real world emissions using SEMS (Sensor-based / Simple Emission Measurement System). Whereas PEMS is a method of sampling and analyzing exhaust gas, SEMS directly attaches NOx sensor and PM sensor to the exhaust pipe and measures the concentration. Although SEMS has a limited number of items that can be measured compared to PEMS, other analyzes are possible by devising the analysis method. This paper focuses on the analysis method of…