Variation and Control of Small Gasoline Engine Emissions Performance in the Plateau Region

2013 ◽  
Vol 726-731 ◽  
pp. 2022-2025
Author(s):  
Chong Shang Li ◽  
Sheng Ji Liu ◽  
Jian Wang
Keyword(s):  
Gasoline Engine ◽  
Quantitative Relationship ◽  
Mixing Ratio ◽  
Engine Emissions ◽  
Plateau Region ◽  
Gasoline Engines ◽  
Emission Regulations ◽  
Air Intake ◽  
Specific Emissions ◽  
And Control

When small gasoline engines using carburettor are operated in the plateau region, the air intake and fuel supply have different decrease with the altitude increase, and the mixture thicken and the emissions increase. Take outboard marine gasoline engine F15 as an example, the quantitative relationship comparing engines operated on the plateau region to on the plain in same mixing ratio are shown, which includes the power, specific fuel consumption, and CO, HC, NOx specific emissions. And fuel system correction methods are come out to meet EPA emission regulations in different altitudes.

A Review of the Applicability of Hydro Fuel to Improve the Engine Performance and Reduce Engine Emissions in Dual-Fuel Technology of Gasoline Engine

2018 ◽  
Vol 7 (3) ◽  
pp. 14
Author(s):  
Thanh Vo Xuan ◽  
Dung Do Van ◽  
Quoc Hoang An
Keyword(s):  
Gasoline Engine ◽  
Engine Performance ◽  
Volume Ratio ◽  
Intake Manifold ◽  
Dual Fuel ◽  
Hydrogen Fuel ◽  
Engine Emissions ◽  
Experimental Conditions ◽  
Gasoline Engines ◽  
Fuel Technology

Hydrogen fuel becomes an alternative fuel because of its advantage properties. Hydrogen fuel can be used in form of H2 or HHO. On the dual-fuel systems, hydrogen may be supplied to engines by injectors or by the differential pressure in the intake manifold. This paper presented the applicability of hydrogen on gasoline engines. The paper analyzed and evaluated the methods of hydrogen fuel applications, the results of the performance and engine emissions of the latest researches in over the world. The experiments were performed at hydrogen volume ratio from 1% to 4.5% and different experimental conditions. The experimental results were compared with only-gasoline engines. The combustion cylinders pressure is increased. The thermal efficiency is increased to 7%. The emission of HC and CO emissions are decreased significantly. NOx is reduced at learn conditions and increased at other conditions.

A Throttle Loss Recovery Concept Using an Expander for a 2.0 Litre Turbocharged Gasoline Engine

2015 ◽  
Author(s):  
P. Lu ◽  
B. Hu ◽  
C. Brace
Keyword(s):  
Pressure Drop ◽  
Gasoline Engine ◽  
Combustion Engine ◽  
Simulation Code ◽  
Gasoline Engines ◽  
Engine Simulation ◽  
Exhaust Heat ◽  
Engine System ◽  
The Cost ◽  
And Control

In the internal combustion engine, a large amount of energy is rejected in the form of exhaust heat without being converted into brake work. Additionally, in gasoline engines, throttle losses are also a considerable disadvantage limiting the capability to achieve higher thermal efficiency. Under part load conditions, both the power demand and engine speed are much lower than the maximum achievable. The throttle is partially closed to restrict inlet air mass flow to regulate the brake power production. To overcome the friction and turbulence losses at the small throttle opening, negative pressure is produced in the manifold at the cost of engine power. This paper explores the effectiveness of an expander installed in the inlet duct of the engine to lessen, even eliminate, the throttle losses by allowing power to be reclaimed from the pressure drop across the expander, which will otherwise be wastefully dissipated across the throttle. In this way the pumping losses are reduced. The engine system was modelled in GT-Power which is a 1-dimensional engine simulation code. The limits in decreasing in pressure drop through the throttle and the power generation from the expander were explored. Together with a turbo machine recovering energy from the exhaust flow, this system was able to enhance the fuel economy by about 5% when operating at 1.75 bar BMEP from 500–3000rpm compared with a conventional turbocharged engine. The influence of the expander machinery on the combustion and the turbocharger performance was also discussed. To achieve the highest performance level, careful optimization of the expander size and control strategy and proper matching with engine system are critical.

scholarly journals Gasoline Engine and Aftertreatment Modeling and Control

2015 ◽  
Vol 137 (12) ◽  
pp. S7-S10
Author(s):  
Mrdjan Jankovic
Keyword(s):  
Control System ◽  
Gasoline Engine ◽  
Precious Metals ◽  
System Component ◽  
Spark Ignition Engines ◽  
Modeling And Control ◽  
Gasoline Engines ◽  
Feed Forward Control ◽  
And Control ◽  
Conversion Efficiencies

This article discusses the design of control system components for gasoline engines. Gasoline or, more precisely, spark ignition engines power a large majority of personal vehicles sold worldwide. A major task for the automakers is to provide good drivability and fuel economy while meeting increasingly stringent emission requirements. Achieving low emissions requires a significant reduction in cold start emissions and employment of catalytic converters to reduce tailpipe emissions once the engine is warmed up. The catalysts are loaded with precious metals – typically platinum, palladium, and rhodium. They achieve very high conversion efficiencies, but only if the engine is operated very close to stoichiometry that corresponds to the air-fuel ratio of about 14.6 for gasoline and of 9 for ethanol. Design of a control system component requires that an appropriate model be developed. The models range from very simple low-order, linear for the inner loop to a partial-differential-equation based model for the catalyst. In general, feedback controllers tolerate and even benefit from simpler models. Feed-forward control, estimation, diagnostics, and failure mode management requires more elaborate models.

scholarly journals Analysis of Driving Dynamics Considering Driving Resistances in On-Road Driving

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3408
Author(s):  
Jingeun Song ◽  
Junepyo Cha
Keyword(s):  
Combustion Engine ◽  
Vehicle Speed ◽  
Driving Dynamic ◽  
Engine Emissions ◽  
Engine Load ◽  
Positive Acceleration ◽  
Emission Regulations ◽  
Transportation Emissions ◽  
Light Duty Vehicles ◽  
Dynamic Variables

Internal combustion engine emissions are a serious worldwide problem. To combat this, emission regulations have become stricter with the goal of reducing the proportion of transportation emissions in global air pollution. In addition, the European Commission passed the real driving emissions–light-duty vehicles (RDE-LDV) regulation that evaluates vehicle emissions by driving on real roads. The RDE test is significantly dependent on driving conditions such as traffic or drivers. Thus, the RDE regulation has the means to evaluate driving dynamics such as the vehicle speed per acceleration (v·apos) and the relative positive acceleration (RPA) to determine whether the driving during these tests is normal or abnormal. However, this is not an appropriate way to assess the driving dynamics because the v⋅apos and the RPA do not represent engine load, which is directly related to exhaust emissions. Therefore, in the present study, new driving dynamic variables are proposed. These variables use engine acceleration calculated from wheel force instead of the acceleration calculated from the vehicle speed, so they are proportional to the engine load. In addition, a variable of driving dynamics during braking is calculated using the negative wheel force. This variable can be used to improve the accuracy of the emission assessment by analyzing the braking pattern.

Diagnosis Research on Main Bearing Wear of Gasoline Engines in Mechanical Engineering

2013 ◽  
Vol 644 ◽  
pp. 304-307 ◽  
Author(s):  
Chang Shun Wang
Keyword(s):  
Gasoline Engine ◽  
Vibration Monitoring ◽  
Analysis Method ◽  
Characteristic Parameters ◽  
Main Bearing ◽  
Vibration Signals ◽  
Gasoline Engines ◽  
Test Spot ◽  
Monitoring Mechanism ◽  
Spectral Analysis Method

The different clearances of main bearing of previously designed on EQ6100 model gasoline engine is diagnosed by means of vibration monitoring mechanism. Breakdown signals of main test on different speed, clearance of main bearing, test spot and weather were analyzed by Spectral Analysis method and compared with normal and abnormal vibration signals. As a result, the characteristic parameters and the identifying methods of breakdown are given. In addition, the problems of fault detection are pointed out.

Tumble Flow Measurements Using Three Different Methods and Its Effects on Fuel Economy and Emissions

2006 ◽  
Author(s):  
Myoungjin Kim ◽  
Sihun Lee ◽  
Wootae Kim
Keyword(s):  
Fuel Economy ◽  
High Performance ◽  
Gasoline Engine ◽  
Exhaust Emissions ◽  
Combustion Stability ◽  
Lean Burn ◽  
Flow Measurements ◽  
Part Load ◽  
Gasoline Engines ◽  
Dynamometer Test

In-cylinder flows such as tumble and swirl have an important role on the engine combustion efficiencies and emission formations. In particular, the tumble flow, which is dominant in-cylinder flow in current high performance gasoline engines, has an important effect on the fuel consumptions and exhaust emissions under part load conditions. Therefore, it is important to know the effect of the tumble ratio on the part load performance and optimize the tumble ratio of a gasoline engine for better fuel economy and exhaust emissions. First step in optimizing a tumble flow is to measure a tumble ratio accurately. In this research the tumble flow was measured, compared and correlated using three different measurement methods: steady flow rig, 2-Dimensional PIV, and 3-Dimensional PTV. Engine dynamometer test was performed to find out the effect of the tumble ratio on the part load performance. Dynamometer test results of high tumble ratio engine showed faster combustion speed, retarded MBT timing, higher exhaust emissions, and a better lean burn combustion stability. Lean limit of the baseline engine was expanded from A/F=18:1 to A/F=21:1 by increasing a tumble ratio using MTV.

Optimization of Mode Switching Timing Control for a Lean-Burn Gasoline Engine With a Prototype Passive SCR System

2018 ◽  
Author(s):  
Dakota Strange ◽  
Pingen Chen ◽  
Vitaly Y. Prikhodko ◽  
James E. Parks
Keyword(s):  
Gasoline Engine ◽  
Nox Reduction ◽  
Cost Effective ◽  
Nox Storage ◽  
Mode Switching ◽  
Timing Control ◽  
Lean Burn ◽  
Gasoline Engines ◽  
Effective Manner ◽  
Passive Scr

Passive selective catalytic reduction (SCR) has emerged as a promising NOx reduction technology for highly-efficient lean-burn gasoline engines to meet stringent NOx emission regulation in a cost-effective manner. In this study, a prototype passive SCR which includes an upstream three-way catalyst (TWC) with added NOx storage component, and a downstream urealess SCR catalyst, was investigated. Engine experiments were conducted to investigate and quantify the dynamic NOx storage/release behaviors as well as dynamic NH3 generation behavior on the new TWC with added NOx storage component. Then, the lean/rich mode-switching timing control was optimized to minimize the fuel penalty associated with passive SCR operation. Simulation results show that, compared to the baseline mode-switching timing control, the optimized control can reduce the passive SCR-related fuel penalty by 6.7%. Such an optimized mode-switching timing control strategy is rather instrumental in realizing significant fuel efficiency benefits for lean-burn gasoline engines coupled with cost-effective passive SCR systems.

scholarly journals Technical Note: Implementation of prescribed (OFFLEM), calculated (ONLEM), and pseudo-emissions (TNUDGE) of chemical species in the Modular Earth Submodel System (MESSy)

2006 ◽  
Vol 6 (3) ◽  
pp. 5485-5504
Author(s):  
A. Kerkweg ◽  
R. Sander ◽  
H. Tost ◽  
P. Jöckel
Keyword(s):  
Chemical Species ◽  
Atmospheric Modeling ◽  
Technical Note ◽  
Mixing Ratio ◽  
Emission Data ◽  
Sources And Sinks ◽  
Emission Fluxes ◽  
Specific Emissions ◽  
The Creation ◽  
Community Modeling

Abstract. We present the submodels OFFLEM, ONLEM, and TNUDGE for the Modular Earth Submodel System (MESSy). Prescribed emissions from input files are handled by OFFLEM. ONLEM deals with online-calculated emissions, i.e., emissions that are calculated during the simulation. The submodel TNUDGE uses the ''tracer nudging'' technique for pseudo-sources and -sinks. For species with highly uncertain emission fluxes and/or with sufficiently long lifetimes, e.g., CH4, it is common to create such pseudo-fluxes by prescribing the observed mixing ratio of the species at a given boundary (e.g., the mixing ratio of methane at the surface, or the ozone mixing ratio at the tropopause). All three submodels substantially simplify the inclusion of emissions into a model. Specific emissions can easily be switched on or off. New prescribed emissions can be included without rewriting any code. New online emissions only require one additional subroutine containing the new parameterization. A major advantage is that input fields at arbitrary resolution can be used. The problem of incompatible grids between emission data and model is overcome by utilizing the MESSy data import interface. To further simplify the creation of new offline emission data, the preprocessing program EDGAR2NC is provided. EDGAR2NC transforms files from the EDGAR format into the netCDF format which is required by OFFLEM. The presented routines are a part of the community modeling project MESSy and can be made available for use to the atmospheric modeling community.

scholarly journals Identification of Ru/Ceria Among Single Atom Ceria Catalysts as a Stable and Superior Material for Abatement of Diesel and Gasoline Engine Pollutants

2020 ◽  
Author(s):  
Konstantin Khivantsev ◽  
Nicholas R. Jaegers ◽  
Libor Kovarik ◽  
Jinshu Tian ◽  
Xavier Isidro Pereira Hernandez ◽  
...  
Keyword(s):  
Gasoline Engine ◽  
No Oxidation ◽  
Oxidation Catalyst ◽  
Single Atom ◽  
Hydrothermal Aging ◽  
Gasoline Engines ◽  
Nox Adsorption ◽  
Ceria Catalysts ◽  
Better Than ◽  
Three Way Catalysis

Atomically dispersed transition metals (Ru, Pd and Pt) have been prepared on CeO<sub>2</sub> and evaluated for NOx/CO abatement applications for diesel and gasoline engines, such as low temperature passive NOx adsorption (PNA), NO and CO oxidation, and three-way-catalysis (TWC). 0.5 wt% Ru/CeO<sub>2</sub> catalyst (Ru is ~27 and ~7 times cheaper than Rh and Pd) shows remarkable PNA performance, better than 1 wt% Pd/Zeolite: it achieves 100% removal of NOx during vehicle cold start. FTIR measurements reveal the formation of stable Ru(NO) complexes as well spill-over of NO to CeO<sub>2</sub> surface via the Ru-O-Ce shuttle, explaining high NO storage. Notably, Ru/ceria survives hydrothermal aging at 750 ⁰C without loss of PNA capacity. It is also a robust NO oxidation catalyst, considerably more active than Pt or Pd/CeO<sub>2</sub>. Expanding the repertoire of Ru/CeO<sub>2</sub> catalytic applications, we further find 0.1 and 0.5 wt% Ru/CeO<sub>2</sub> to be excellent TWC catalysts, rivaling best single-atom Rh supported materials. Our study pushes the frontier of precious metal atom economy for environmental catalysis from uber expensive Rh/Pd/Pt to more sustainable cheaper Ru and highlights the utility of single-atom catalysts for industrially relevant applications.

Compressor Design for Multi-Point Operating Conditions of Turbocharged Gasoline Engines

2010 ◽  
Author(s):  
Tao Chen ◽  
Yangjun Zhang ◽  
Xinqian Zheng ◽  
Weilin Zhuge
Keyword(s):  
Internal Combustion Engines ◽  
Gasoline Engine ◽  
Design Method ◽  
Pressure Ratio ◽  
Operating Conditions ◽  
Combustion Engines ◽  
Gasoline Engines ◽  
Compressor Design ◽  
Operating Points ◽  
Load Conditions

Turbocharger compressor design is a major challenge for performance improvement of turbocharged internal combustion engines. This paper presents a multi-point design methodology for turbocharger centrifugal compressors. In this approach, several design operating condition points of turbocharger compressor are considered according to total engine system requirements, instead of one single operating point for traditional design method. Different compressor geometric parameters are selected and investigated at multi-point operating conditions for the flow-solutions of different design objectives. The method has been applied with success to a small centrifugal compressor design of a turbocharged gasoline engine. The results show that the consideration of several operating points is essential to improve the aerodynamic behavior for the whole working range. The isentropic efficiency has been increased by more than 5% at part-load conditions while maintaining the pressure ratio and flow range at full-load conditions of the gasoline engine.

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