CAI Combustion of Gasoline and its Mixture with Ethanol in a 2-Stroke Poppet Valve DI Gasoline Engine

Abstract

h i g h l i g h t sCAI combustion is achieved in a 2-stroke poppet valve GDI engine. Gasoline and its mixture with ethanol are used as the fuel on the engine. The effect of ethanol content on operating range, combustion and emissions are analysed. a b s t r a c t Controlled Auto Ignition (CAI), also known as Homogeneous Charge Compression Ignition (HCCI), is one of the most promising combustion technologies to reduce the fuel consumpt ion and NOx emissions . Currently, CAI combustion is constrained at part load operation conditions becau se of misfire at low load and knocking combustion at high load, and the lack of effective means to control the combustion process. Extending its ope rating range including high load boundary towards full load and low load boun dary towards idle in order to allow the CAI engine to meet the demand of whole vehicle driving cycles, has become one of the key issues facing the industrialisation of CAI/HCCI technology. Furthermore, this combustion mode should be compatible to different fuels, and can switch back to conventional spark ignition operation when necessary. In this paper, the CAI operation is demonstrated on a 2-stroke gasoline direct injection (GDI) engine equipped with a poppet valve train. The results shown that the CAI combustion can be readily achieved in the 2-stroke cycle of a poppet valve engine and the range of CAI combustion can be significantly extended compared to the 4-stroke cycle operation . In addition, the effect s of ethanol concentration on 2-stroke CAI operational range, combustion proce ss, emissions and efficiencies are studied and presented. a r t i c l e i n f o

Experimental investigation of the influence of internal and external EGR on the combustion characteristics of a controlled auto-ignition two-stroke cycle engine

“…The effect of exhaust gas recirculation (EGR) on the CAI combustion characteristics was examined using exhaust port throttling strategy when the engine was run under WOT condition [46,47]. The effect of utilizing internal EGR by means of the negative valve overlap strategy (rebreathing) has been investigated in a switchable two/four-stroke engine [48][49][50]. The effect of EGR employed in the CAI combustion process was investigated numerically and experimentally [29,32,51].…”

Analisa Performa Mesin Dan Kadar Emisi Gas Buang Kendaraan Bermotor Dengan Memanfaatkan Bioetanol Dari Bahan Baku Singkong Sebagai Bahan Bakar Alternatif Campuran Pertalite

“…Selain itu, lebih tinggi panas campuran bensin bioetanol membuat campuran yang lebih baik, yang mengarah ke pembakaran yang lebih sempurna. Sehingga mengurangi masalah lingkungan, meningkatkan ekonomi pertanian dan menghindari ketergantungan pada negara-negara bahan bakar penghasil fosil [3].…”

Chemical kinetic analysis of in-cylinder ion current generation under direct water injection within internal combustion Rankine cycle engine

“…Compare with the battery electric vehicle (BEV) and fuel cell vehicle (FCV), the main obstacles of ICE are relatively low tank-to-wheel (TTW) efficiency and in-use emissions [1][2]. While the brake thermal efficiency (BTE) of modern commercial petrol ICE has improved significantly by implementation of advanced engine optimization technologies including lean/diluent combustion [3], Atkinson/Miller cycle [4], intensive in-cylinder tumble flow [5], variable compression ratio [6], controllable auto-ignition [7], etc., the overall TTW efficiency remains under 45% [8]. The requirement for novel combustion concept which is capable in realizing extreme high thermal efficiency while achieving zero emission is becoming more and more urgent.…”