Combustion and Emission Enhancement of a Spark Ignition Two-Stroke Cycle Engine Utilizing Internal and External Exhaust Gas Recirculation Approach at Low-Load Operation

Abstract

Two-stroke cycle engines have always been prominent due to their distinctive advantage incorporating high power-to-weight ratio, however the drawbacks are poor combustion efficiency, fuel short-circuiting and excessive emission of uHC and CO. These problems are apparent at low-load and speed regions and are the major obstacle to their global acceptance. The deficiencies can be addressed by increasing the in-cylinder average charge temperature employing Exhaust Gas Recirculation (EGR). An experimental study is conducted to investigate the influence of utilizing EGR techniques, including Internal and External EGR, on combustion misfiring occurrence, combustion stability and exhaust emissions using a single cylinder two-stroke SI engine at idling, low and mid-load conditions. From the results, it is observed since the average in-cylinder charge temperature is increased, due to utilizing EGRs, engine’s low and mid-load irregular combustions (misfire) and exhaust emissions are remarkably supressed and almost all of misfire cycles eliminated depending on the percentage of EGRs. In terms of combustion stability, it is agreed in general the application of EGRs improves the cyclic variation of IMEP, Pmax and CA10 compared to conventional operation. However, applying Ex-EGR compared to In-EGR will deteriorate cyclic variability of IMEP and CA10.

Determining the characteristics for the rational adjusting of an fuel-air mixture composition in a two-stroke engine with internal carburation

“…The use of DFI and exhaust gas recirculation is one of the promising ways to reduce fuel consumption and emissions of harmful substances from exhaust gases in a two-stroke SIE [24,25]. However, the issues connected with the change of the amount of recirculated exhaust gas relate to a specific method of organizing the operating process and cannot be fully extended to other operating processes that differ from it.…”

Electric Vehicle Modelling for Future Technology and Market Penetration Analysis

“…The idea of driving vehicles with electric motors (EM) is not recent. EVs held 29% of the total vehicles and were preferred over ICE until the early 1900 (Andwari et al, 2018;Mahmoudzadeh Andwari et al, 2019). However, due to very low oil prices, ICE gained momentum and monopoly of the market.…”

Air-Fuel Mixture Temperatures with Light and Heavy Fuels for Effective Spark Ignition Engine Work

“…The effect of heating heavy fraction fuels in the SI engine has been previously studied in carburettor and injection FSS´s. Research [11][12][13][14][15][16][17][18][19][20] focuses mainly on reducing the hazardous components that are contained within exhaust gases, solving cold start problems, and reducing the engine's fuel consumption rate, as well as on the combustion of various AFM's in the engine's cylinder. In addition, the use of heat energy in different heat exchangers (HEX) is something that has been studied in the past, but the research has focused more on the recovery of heat energy from exhaust gases and the study of cooled exhaust gases [21][22][23][24][25][26][27][28].…”