Ignition control in a gasoline compression ignition engine with ozone addition combined with a two-stage direct-injection strategy

Abstract

To control the ignition timing in a gasoline compression ignition (GCI) engine, ozone (O3) was introduced into the intake air. The O-radicals are decomposed from the O3 above 550 K during the compression stroke, and combine into oxygen (O2) in a very short time.The authors adopted two-stage direct injection to mix the fuel injected into the cylinder at very early timings with the O-radicals, before a reduction of the O-radicals would take place. The ignition timing of the second fuel injection for the main combustion is controlled by the heat release from the first fuel injection. In this paper, engine experiments were performed to examine the feasibility of the ignition control with a primary reference fuel, octane number 90 (PRF90). The O3 concentration, the quantity, and the timing of the first injection were changed as experimental parameters. The results showed that a very small quantity of O3, tens of ppm, is sufficient to promote the heat release of the first injected fuel. The heat release increases with the O3 concentration and

Optimization of gasoline compression ignition combustion with ozone addition and two-stage direct-injection at middle loads

“…In the previous studies, ozone was applied to improve low load operation of GCI. 22,25 To examine the benefit of the ozone addition at higher loads, the total injection quantity was set to 29 mg/cycle, and the resultant indicated mean effective pressure (IMEP) was around 0.67 MPa, at the conditions here. As the ozone chemistry mainly affects the low temperature oxidation reaction (LTOR), its interaction depends on the equivalence ratio.…”

“…In the previous study, retarding the first injection timing u inj.1st decreases the quantity of heat release by the first injection, even remarkable so later than 260 °CA ATDC, showing that the O-radicals decomposed from ozone missed an opportunity to react with the first injection. 22 Considering this and the fact that too early injection may cause wall-wetting, the first injection timing u inj.1st was set at 268 °CA ATDC. The second injection timing u inj.2nd was advanced from 6 °CA ATDC until the local maximum of the indicated thermal efficiency was identified.…”

Detailed Injection Strategy Analysis of a Heavy-Duty Diesel Engine Running on Rape Methyl Ester

“…The application of biofuels in internal combustion engines (ICEs) is today a relevant issue as these types of engines are widely used for stationary power plants and in the transport sector. The main task for researchers today is to search for advanced combustion concepts [1][2][3] and alternative fuels to face the issues impacted by the traditional technologies [4,5].…”

Unaccounted Heat Distribution in a Variable Compression Ratio Internal Combustion Engine

“…Dominant the set-off amount in conserving with engine operating circumstances is principal to optimize the air-entrainment into the fuel spray. Factors moving the set-off amount [2] additionally because the information of the flame set-off had been staggeringly studied. it's emerge as originated that reducing close density with low boosting and what is more the element awareness with higher exhaust gas recirculation (EGR) makes it potential to increase the set-off size.…”

“…yet, partaking in ignition manage over an intensive type of engine plenty and rotation speeds continues to be arduous because the ignition temporal order of the GCI powerfully depends at the gas big variety and therefore the time when of injection, and an additional manner to control the ignition temporal order, that is neutral of the injection temporal order, would be needed. One manner to gather that's to form use of 2 fuels that have precise relativities as applied in reactivity managed compression ignition (RCCI) engines [2], however this methodology needs two fuel tanks that makes it tough to enforce in engine programs used for transportation. Depleting fossil fuel reserves, developing fossil fuel costs, danger to the atmosphere from exhaust emissions and world warming wishes a vast international curiosity in developing substitute on fossil fuel fuels for engines [3].…”