An assessment of the dual-mode reactivity controlled compression ignition/conventional diesel combustion capabilities in a EURO VI medium-duty diesel engine fueled with an intermediate ethanol-gasoline blend and biodiesel. (1st September 2016)

• Record Type: Journal Article
• Authors: Benajes, Jesús; García, Antonio; Monsalve-Serrano, Javier; Balloul, Iyad; Pradel, Gérard
• Is Part Of: Energy conversion and management. Volume 123(2016)
• Page Start: 381
• Page End: 391
• Publication Date: 2016-09-01
• Subjects: Reactivity controlled compression ignition -- Dual-fuel combustion -- Dual-mode operation -- EURO VI emissions -- Biofuels; ASTM American Society of Testing and Materials -- ATDC After Top Dead Center -- CAD Crank Angle Degree -- CA10 crank angle at 10% mass fraction burned -- CA50 crank angle at 50% mass fraction burned -- CDC conventional diesel combustion -- CO carbon monoxide -- CR compression ratio -- DI direct injection -- DPF diesel particulate filter -- ECU electronic control unit -- EGR exhaust gas recirculation -- EOI end of injection -- EU European Union -- EVO exhaust valve open -- FSN Filter Smoke Number -- HC hydro carbons -- HCCI homogeneous charge compression ignition -- MPRR maximum pressure rise rate -- IMEP indicated mean effective pressure -- ISFC indicated specific fuel consumption -- IVC intake valve close -- IVO intake valve open -- LNT lean NOx trap -- LTC low temperature combustion -- MCE multi cylinder engine -- OEM original equipment manufacturer -- ON octane number -- PFI port fuel injection -- PPC partially premixed charge -- PRR pressure rise rate -- RCCI reactivity controlled compression ignition -- RED renewable energy directive -- RoHR rate of heat release -- RI ringing intensity -- SOC start of combustion -- SOI start of injection -- SCE single cylinder engine -- SCR selective catalytic reduction; Direct energy conversion -- Periodicals; Energy storage -- Periodicals; Energy transfer -- Periodicals; Énergie -- Conversion directe -- Périodiques; Direct energy conversion; Periodicals; 621.3105
• DOI: 10.1016/j.enconman.2016.06.059
• Languages: English
• ISSNs: 0196-8904

Abstract

Highlights: Reactivity controlled compression ignition regime utilized from 25% to 35% load. Dual-mode reduces the regeneration periods of the diesel particulate filter. The use of near-term available biofuels allows good performance and emissions. Dual-mode leads to 2% greater efficiency than diesel combustion at high engine speeds. Abstract: This work investigates the capabilities of the dual-mode reactivity controlled compression ignition/conventional diesel combustion engine operation to cover the full operating range of a EURO VI medium-duty diesel engine with compression ratio of 17.5:1. This concept is based on covering all the engine map switching between the reactivity controlled compression ignition and the conventional diesel combustion operating modes. Specifically, the benefits of reactivity controlled compression ignition combustion are exploited whenever possible according to certain restrictions, while the conventional diesel combustion operation is used to cover the zones of the engine map in which the reactivity controlled compression ignition operation is limited. The experiments were conducted using a single-cylinder research diesel engine derived from the multi-cylinder production engine. In addition, considering the mandatory presence of biofuels in the future context of road transport and the ability of ethanol to be blended with gasoline, the low reactivity fuel used in the study is a blend of 20% ethanol by volume with 80% of 95 octane number gasoline. Moreover, a diesel containing 7% of biodiesel has been used as high reactivity fuel. Firstly, a reactivity controlled compression ignition mapping is performed to check the operational limits of the concept in this engine platform. Later, based on the results, the potential of the dual-mode concept is discussed. Results suggest that, under the constraints imposed, reactivity controlled compression ignition combustion can be utilized between 25% and 35% load. In this region of the map, reactivity controlled compression ignition can provide up to 2% increased gross indicated efficiency than conventional diesel combustion, but led to lower efficiency at low engine speeds. In addition, it was demonstrated that the regeneration periods of the diesel particulate filter during dual-mode operation can be reduced more than twice, which entails a great reduction of the diesel fuel amount injected in the exhaust line.