Combustion reaction kinetics of biodiesel/n-butanol blends: Experiments in an ultrahigh-pressure rapid compression machine
Combustion reaction kinetics of biodiesel/n-butanol blends: Experiments in an ultrahigh-pressure rapid compression machine
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DOI：
10.1016/j.combustflame.2022.112313
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发表时间：
2022-11
影响因子：
4.4
通讯作者：
Wei Zhou;Yongxiang Zhang;Yueying Liang;Liang Yu;Xingcai Lu
中科院分区：
文献类型：
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作者：
Wei Zhou;Yongxiang Zhang;Yueying Liang;Liang Yu;Xingcai Lu
在发动机中燃烧含氧烃生物燃料是节约能源和减少碳排放的可行途径。正丁醇和生物柴油是两种具有代表性的生物燃料，引起了人们的广泛关注。采用新型超高压快速压缩机，研究了不同正丁醇体积分数（40%、60%、80%）的正丁醇与生物柴油（一种废弃食用油）的混合物的自燃特性。在10/20/40/60 bar宽压力、0.3/0.5/1.0当量比和700 - 970 K温度范围内精确测量了共混物的点火延迟时间。实验结果表明，在所研究的条件下，无论掺混比如何，着火延迟时间都随压力和当量比的增大而减小。在820 K以下，随着正丁醇含量的增加，着火延迟时间略有延长。但随着温度的进一步升高，不同共混物的滞燃期越来越接近，并有交叉的趋势。对生物柴油的组成进行了定量分析，并开发了替代燃料。在已有的461个物种和18，217个反应的详细机理的基础上，提出了一个优化的机理。仿真结果表明，优化的机制更好地捕捉到的温度，压力和混合比在整个温度范围内的测量点火延迟时间的依赖性相比，原来的机制。最后，物种进化和灵敏度分析进行了顺序与优化的机制，给动力学洞察生物柴油和正丁醇之间的化学相互作用。本文的实验数据和模型结果为了解生物柴油/正丁醇混合燃料的燃烧反应动力学提供了基础。
Burning oxygenated hydrocarbon biofuels in engines is a viable path for saving energy and reducing carbon emissions. N-butanol and biodiesel are two representative biofuels and have attracted widespread interest. In this study, the blends of n-butanol and biodiesel (a waste cooking oil) with different n-butanol ratios (40%, 60%, 80% by volume) were adopted to study their autoignition characteristics in a newly developed ultrahigh-pressure rapid compression machine. The ignition delay times of the blends were precisely measured under wide pressures of 10/20/40/60 bar, equivalence ratios of 0.3/0.5/1.0, and a temperature range of 700–970 K. Experimental results show that the ignition delay time decreases with the increase of pressure and equivalence ratio at the investigated conditions regardless the blending ratios. It is also found that the ignition delay time becomes slightly longer with the increasing n-butanol ratio in the blends at temperatures below 820 K. However, as the temperature further increases, the ignition delay times of different blends get closer and has a crossover tendency. The composition of the biodiesel was quantitively analyzed and a surrogate fuel was developed. An optimized mechanism was proposed based on a documented detailed mechanism with 461 species and 18,217 reactions. Simulation results show that the optimized mechanism better captures the dependence of the measured ignition delay times on temperature, pressure, and blending ratios over the entire temperature range compared to the original mechanism. In the end, species evolution and sensitivity analysis were performed sequentially with the optimized mechanism to give kinetics insight into the chemical interaction between biodiesel and n-butanol. The experimental data and modeling results reported here provide a basis for understanding the combustion reaction kinetics of biodiesel/n-butanol blending fuels.