scholarly journals Comparisons of Laboratory and On-Road Type-Approval Cycles with Idling Emissions. Implications for Periodical Technical Inspection (PTI) Sensors

Sensors ◽  
2020 ◽  
Vol 20 (20) ◽  
pp. 5790 ◽  
Author(s):  
Barouch Giechaskiel ◽  
Tero Lähde ◽  
Ricardo Suarez-Bertoa ◽  
Victor Valverde ◽  
Michael Clairotte
Keyword(s):  
Direct Injection ◽  
Spark Ignition ◽  
Gasoline Direct Injection ◽  
Compression Ignition ◽  
Particulate Filters ◽  
Technical Inspection ◽  
Diesel Vehicles ◽  
Type Approval ◽  
Road Type ◽  
Technical Specifications

For the type approval of compression ignition (diesel) and gasoline direct injection vehicles, a particle number (PN) limit of 6 × 1011 p/km is applicable. Diesel vehicles in circulation need to pass a periodical technical inspection (PTI) test, typically every two years, after the first four years of circulation. However, often the applicable smoke tests or on-board diagnostic (OBD) fault checks cannot identify malfunctions of the diesel particulate filters (DPFs). There are also serious concerns that a few high emitters are responsible for the majority of the emissions. For these reasons, a new PTI procedure at idle run with PN systems is under investigation. The correlations between type approval cycles and idle emissions are limited, especially for positive (spark) ignition vehicles. In this study the type approval PN emissions of 32 compression ignition and 56 spark ignition vehicles were compared to their idle PN concentrations from laboratory and on-road tests. The results confirmed that the idle test is applicable for diesel vehicles. The scatter for the spark ignition vehicles was much larger. Nevertheless, the proposed limit for diesel vehicles was also shown to be applicable for these vehicles. The technical specifications of the PTI sensors based on these findings were also discussed.

Control of a spark ignition homogeneous charge compression ignition mode transition on a gasoline direct injection engine

2007 ◽  
Vol 221 (7) ◽  
pp. 867-875 ◽  
Author(s):  
G Tian ◽  
Z Wang ◽  
Q Ge ◽  
J Wang ◽  
S Shuai
Keyword(s):  
Homogeneous Charge Compression Ignition ◽  
Direct Injection ◽  
Spark Ignition ◽  
Gasoline Direct Injection ◽  
Compression Ignition ◽  
Combustion Mode ◽  
Key Issues ◽  
Cam Profile ◽  
Negative Valve Overlap ◽  
Homogeneous Charge

The hybrid combustion mode is an ideal operation strategy for a gasoline homogeneous charge compression ignition (HCCI) engine. A stable and smooth spark ignition (SI)/HCCI switch has been an issue in the research on multimode combustion. In this paper, the switch process has two key issues; the cam profile and throttle opening. With the developed two-stage cam system, the valve phase strategy can be switched within one engine cycle, from the normal cam profile for the SI mode to a negative valve overlap (NVO) profile for the HCCI mode, or vice versa. For a smoother and more stable switch, the throttle change was separated from the cam profile switch, which was called the stepped switch. The effect of throttle opening on HCCI combustion was studied, and the results showed that the concept of the stepped switch was reliable. With gasoline direct injection (GDI) the combustion mode switches from both SI and HCCI sides were smooth, rapid, and robust, without any abnormal combustion such as knocking and misfiring.

Study of Multimode Combustion System With Gasoline Direct Injection

2006 ◽  
Vol 129 (4) ◽  
pp. 1079-1087 ◽  
Author(s):  
Zhi Wang ◽  
Jian-Xin Wang ◽  
Shi-Jin Shuai ◽  
Yan-Jun Wang ◽  
Guo-Hong Tian ◽  
...  
Keyword(s):  
Fuel Injection ◽  
Direct Injection ◽  
Spark Ignition ◽  
Gasoline Direct Injection ◽  
Compression Ignition ◽  
Combustion System ◽  
Stratified Charge ◽  
Part Load ◽  
Valve Overlap ◽  
Homogeneous Charge

In this paper, a multimode combustion system was developed in a gasoline direct injection engine. A two-stage fuel-injection strategy, including flexible injection timings and flexible fuel quantity, is adopted as a main means to form desired mixture in the cylinder. The combustion system can realize five combustion modes. The homogeneous charge spark ignition (HCSI) mode was used at high load to achieve high-power output density; stratified charge spark ignition (SCSI) was adopted at intermediate load to get optimum fuel economy; stratified charge compression ignition (SCCI) was introduced at transient operation between SI and CI mode. Homogeneous charge compression ignition (HCCI) was utilized at part load to obtain ultralow emissions. Reformed charge compression ignition (RCCI) was imposed at low load to extend the HCCI operation range. In SI mode, the stratified concentration is formed by introducing a second fuel injection in the compression stroke. This kind of stratified mixture has a faster heat release than the homogeneous mixture and is primarily optimized to reduce the fuel consumption. In CI mode, the cam phase configurations are switched from positive valve overlap to negative valve overlap (NVO). The test results reveal that the CI combustion is featured with a high gradient pressure after ignition and has advantages in high thermal efficiency and low NOx emissions over SI combustion at part load.

scholarly journals Catalyzed Gasoline Particulate Filters Reduce Secondary Organic Aerosol Production from Gasoline Direct Injection Vehicles

2019 ◽  
Vol 53 (6) ◽  
pp. 3037-3047 ◽  
Author(s):  
Patrick Roth ◽  
Jiacheng Yang ◽  
Emmanuel Fofie ◽  
David R. Cocker ◽  
Thomas D. Durbin ◽  
...  
Keyword(s):  
Secondary Organic Aerosol ◽  
Direct Injection ◽  
Organic Aerosol ◽  
Gasoline Direct Injection ◽  
Particulate Filters

Simulations of Multi-Mode Combustion Regimes Realizable in a Gasoline Direct Injection Engine

2020 ◽  
Author(s):  
Sayop Kim ◽  
Riccardo Scarcelli ◽  
Yunchao Wu ◽  
Johannes Rohwer ◽  
Ashish Shah ◽  
...  
Keyword(s):  
Mixed Mode ◽  
Direct Injection ◽  
Flow Property ◽  
Gasoline Direct Injection ◽  
Combustion Model ◽  
Compression Ignition ◽  
Fuel Blend ◽  
Combustion Dynamics ◽  
Low Load ◽  
Multi Mode

Abstract Lean and dilute gasoline compression ignition (GCI) operation in spark ignition (SI) engines are an attractive strategy to attain high fuel efficiency and low NOx levels. However, this combustion mode is often limited to low-load engine conditions due to the challenges associated with autoignition controllability. In order to overcome this constrain, multi-mode (MM) operating strategies, consisting of advanced compression ignition (ACI) at low load and conventional SI at high load, have been proposed. In this 3-D CFD study the concept of multi-mode combustion using two RON98 gasoline fuel blends (Co-Optima Alkylate and E30) in a gasoline direct injection (GDI) engine were explored. To this end, a new reduced mechanism for simulating the kinetics of E30 fuel blend is introduced in this study. To cover the varying engine load demands for multi-mode engines, primary combustion dynamics observed in ACI and SI combustion modes was characterized and validated against experimental measurements. In order to implement part-load conditions, a strategy of mode-transition between SI and ACI combustion (i.e., mixed-mode combustion) was then explored numerically by creating a virtual test condition. The results obtained from the mixed-mode simulations highlight an important feature that deflagrative flame propagation regime coexists with ignition-assisted end-gas autoignition. This study also identifies a role of turbulent flow property adjacent to premixed flame front in characterizing the mixed-mode combustion. The employed hybrid combustion model was verified to perform simulations aiming at suitable range of multi-mode engine operations.

Numerical Simulations of Hollow Cone Injection and Gasoline Compression Ignition Combustion With Naphtha Fuels

2015 ◽  
Author(s):  
Jihad A. Badra ◽  
Jaeheon Sim ◽  
Ahmed Elwardany ◽  
Mohammed Jaasim ◽  
Yoann Viollet ◽  
...  
Keyword(s):  
Experimental Data ◽  
Direct Injection ◽  
Gasoline Direct Injection ◽  
Experimental Investigations ◽  
Attractive Alternative ◽  
Spray Parameters ◽  
Compression Ignition ◽  
Hollow Cone ◽  
Modeling Framework ◽  
Primary Reference

Gasoline compression ignition (GCI), also known as partially premixed compression ignition (PPCI) and gasoline direct injection compression ignition (GDICI), engines have been considered an attractive alternative to traditional spark ignition engines. Lean burn combustion with the direct injection of fuel eliminates throttle losses for higher thermodynamic efficiencies, and the precise control of the mixture compositions allows better emission performance such as NOx and particulate matter (PM). Recently, low octane gasoline fuel has been identified as a viable option for the GCI engine applications due to its longer ignition delay characteristics compared to diesel and lighter evaporation compared to gasoline fuel [1]. The feasibility of such a concept has been demonstrated by experimental investigations at Saudi Aramco [1, 2]. The present study aims to develop predictive capabilities for low octane gasoline fuel compression ignition engines with accurate characterization of the spray dynamics and combustion processes. Full three-dimensional simulations were conducted using CONVERGE as a basic modeling framework, using Reynolds-averaged Navier-Stokes (RANS) turbulent mixing models. An outwardly opening hollow-cone spray injector was characterized and validated against existing and new experimental data. An emphasis was made on the spray penetration characteristics. Various spray breakup and collision models have been tested and compared with the experimental data. An optimum combination has been identified and applied in the combusting GCI simulations. Linear instability sheet atomization (LISA) breakup model and modified Kelvin-Helmholtz and Rayleigh-Taylor (KH-RT) break models proved to work the best for the investigated injector. Comparisons between various existing spray models and a parametric study have been carried out to study the effects of various spray parameters. The fuel effects have been tested by using three different primary reference fuel (PRF) and toluene primary reference fuel (TPRF) surrogates. The effects of fuel temperature and chemical kinetic mechanisms have also been studied. The heating and evaporative characteristics of the low octane gasoline fuel and its PRF and TPRF surrogates were examined.

Development of Gasoline Direct Injection Engine for Improving Brake Thermal Efficiency Over 44%

2020 ◽  
Vol 142 (10) ◽  
Author(s):  
Dongwon Jung ◽  
Byeongseok Lee ◽  
Jinwook Son ◽  
Soohyung Woo ◽  
Youngnam Kim
Keyword(s):  
Thermal Efficiency ◽  
Direct Injection ◽  
Stability Limit ◽  
Spark Ignition ◽  
Gasoline Direct Injection ◽  
Brake Thermal Efficiency ◽  
Gasoline Direct Injection Engine ◽  
Combustion Duration ◽  
Test Engine ◽  
Gas Recirculation

Abstract This study demonstrates the effects of technologies applied for the development of gasoline direct injection (GDI) engine for improving the brake thermal efficiency (BTE). The test engine has a relatively high stroke to bore ratio of 1.4 with a displacement of 2156 cm3. All experiments have been conducted for stoichiometric operation at 2000 RPM. First, since compression ratio (CR) is directly related to the thermal efficiency, four CR were explored for operation without exhaust gas recirculation (EGR). Then, for the same four CR, EGR was used to suppress the knock occurrence at high loads, and its effect on initial and main combustion duration was compared. Second, the shape of intake port was revised to increase tumble flow for reducing combustion duration, and extending EGR-stability limit further. Then, as an effective method to ensure stable combustion for EGR-diluted stoichiometric operation, the use of twin spark ignition (SI) system is examined by modifying both valve diameters of intake and exhaust, and its effect is compared against that of single spark ignition. In addition, the layout of twin spark ignition was also examined for the location of front-rear and intake-exhaust. To get the maximum BTE at high load, 12 V electronic super charger (eSC) was applied. Under the condition of using 12 V eSC, the effect of intake cam duration was identified by increasing from 260 deg to 280 deg. Finally, 48 V eSC was applied with the longer intake camshaft duration of 280 deg. As a result, the maximum BTE of 44% can be achieved for stoichiometric operation with EGR.

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