Abstract

It is well known that acetylene has a wide flammability and is readily available and low-cost non-crude oil derivative fuel. According to the property of low motor octane number, the acetylene cannot be used alone in the internal combustion engine. Research has shown that the introduction of biodiesel results in a substantial reduction in the use of conventional fossil fuels and also in the amount of emissions. This study focuses on performance improvement and emission reduction of conventional diesel engine using acetylene gas as a low-reactivity fuel (LRF) and B20 mahua biodiesel as a high-reactivity fuel (HRF) in the reactivity controlled compression ignition (RCCI) mode. The computational fluid dynamics (CFD) principle is used to evaluate the optimal angle of the LRF injector to achieve better fluid flow mixing pattern in the inlet manifold. From the CFD simulation, an optimal LRF injection angle of 45° is defined in the intake manifold. The modified intake manifold engine is tested for performance, emission and combustion characteristics at different flow rates of acetylene through the injector. It is observed that the brake thermal efficiency (BTE) is increased by about 3.7% at a flow rate of 4 liters per minute (LPM) of acetylene injection in RCCI combustion mode compared to conventional biodiesel operation and significant decreases in polluting components such as smoke opacity, oxides of nitrogen (NO_x), hydrocarbon (HC) and carbon monoxide (CO) are reduced by about 10%, 7.6%, 13.4% and 28.7%.

Graphic abstract

中文翻译：

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通过进气歧管喷射减少乙炔气和生物柴油在柴油机中的排放

摘要

众所周知，乙炔具有广泛的可燃性，并且容易获得并且是低成本的非原油衍生燃料。根据低电动机辛烷值的性质，乙炔不能单独用于内燃机中。研究表明，引入生物柴油可大大减少传统化石燃料的使用，并减少排放量。这项研究的重点是在以反应性控制的压缩点火（RCCI）模式使用乙炔气作为低反应性燃料（LRF）和B20 mahua生物柴油作为高反应性燃料（HRF）的常规柴油机上提高性能和减少排放。计算流体动力学（CFD）原理用于评估LRF喷射器的最佳角度，以实现进气歧管中更好的流体流动混合方式。通过CFD仿真，在进气歧管中定义了45°的最佳LRF喷射角。修改后的进气歧管发动机在通过喷油器的不同乙炔流量下的性能，排放和燃烧特性均经过测试。可以观察到，与常规生物柴油操作相比，在RCCI燃烧模式下以乙炔喷射每分钟4升（LPM）的乙炔喷射流量，制动热效率（BTE）提高了约3.7％，并且污染成分（例如烟）显着降低不透明，氮氧化物（NO_X），碳氢化合物（HC）和一氧化碳（CO）是由约10％，7.6％，13.4％和28.7％减少。

图形摘要