Experimental investigation on RCCI heat transfer in a light-duty diesel engine with different fuels: Comparison versus conventional diesel combustion. (5th November 2018)

• Record Type: Journal Article
• Authors: Olmeda, Pablo; García, Antonio; Monsalve-Serrano, Javier; Lago Sari, Rafael
• Is Part Of: Applied thermal engineering. Volume 144(2018)
• Page Start: 424
• Page End: 436
• Publication Date: 2018-11-05
• Subjects: Reactivity controlled compression ignition -- Dual-fuel combustion -- Efficiency -- Internal combustion engine -- Ethanol; ATDC after top dead center -- BTDC before top dead center -- CAD crank angle degree -- CA50 crank angle at 50% mass fraction burned -- CDC conventional diesel combustion -- CI compression ignition -- CO carbon monoxide -- DOC diesel oxidation catalyst -- DI direct injection -- DPF diesel particulate filter -- EGR exhaust gas recirculation -- EOI end of injection -- EVO exhaust valve open -- FSN filter smoke number -- HC hydro carbons -- HCCI homogeneous charge compression ignition -- HRF high reactivity fuel -- ICE internal combustion engine -- IMEP indicated mean effective pressure -- IVC intake valve close -- LRF low reactivity fuel -- LTC low temperature combustion -- NOx nitrogen oxides -- ON octane number -- PCI premixed compression ignition -- PFI port fuel injection -- PPC partially premixed charge -- PRR pressure rise rate -- RCCI reactivity controlled compression ignition -- SOC start of combustion -- SCE single cylinder engine -- SCR selective catalytic reduction -- TPA three-pressure analysis; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2018.08.082
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: Light-duty research engine instrumented with 25 K-type thermocouples. Gasoline and E85 leads to similar results in terms heat transfer. RCCI has higher bulk temperature than conventional diesel combustion. RCCI reduces the heat transfer versus conventional diesel combustion by 13%. Abstract: Reactivity controlled compression ignition (RCCI) combustion has demonstrated to be able to avoid the NOx-soot trade-off appearing during conventional diesel combustion (CDC), with similar or better thermal efficiency than CDC under a wide range of operating conditions. The high thermal efficiency of RCCI is explained by the combination of a short-duration and well-phased combustion process, which maximizes the fuel-to-work conversion efficiency, together with relatively low combustion temperatures, which increases the specific heat ratio during expansion and reduces thermal gradients for heat transfer losses. The objective of this work is to study the RCCI heat transfer characteristics and compare them to those of the CDC regime. To do this, a single-cylinder light-duty research engine instrumented with 25 K-type thermocouples distributed among the cylinder head and cylinder liner is used. First, the influence of some engine settings on the RCCI heat transfer phenomenon is explored by means of parametric sweeps. Later, the RCCI heat transfer characteristics are compared for two different low reactivity fuels (LRF), gasoline and E85. Finally, the heat transfer characteristics of RCCI and CDC combustion regimes are compared at some representative operating points in matched load conditions. The results show that both LRF tested are suitable to be used in RCCI giving similar results in terms of energy usage. Moreover, the ability of RCCI combustion in exploiting the fuel energy to extract useful work is demonstrated, reducing by 13% the heat transfer versus CDC.