论文部分内容阅读
将多环芳烃(PAH)骨架模型与甲苯参比燃料(TRF)氧化模型耦合,构建了一个新的TRF-PAH骨架模型.以新的TRF-PAH骨架模型作为燃料燃烧的气相化学反应模型,基于不同分子结构的燃料氧化过程中生成PAHs和碳烟的路径也不同的研究结论,本文进一步优化了以PAHs为碳烟前驱生成物的碳烟半经验模型.通过甲苯在流动反应器、搅拌反应器和激波管中的氧化/裂解实验验证发现,新的TRF-PAH骨架模型可以相对准确地预测小分子PAHs和重要中间组分的浓度.通过对比烷烃和芳香烃氧化过程中生成苯的计算值可以发现,燃料的分子结构对PAHs的生成路径影响很大.另外,改进后的碳烟模型利用甲苯、正庚烷/甲苯及异辛烷/甲苯混合物为燃料的激波管中裂解和氧化实验验证,结果表明在较宽的工况内碳烟模拟值与实验值吻合较好.最后,将新的碳烟模型应用于KIVA程序,模拟以TRF20为燃料的柴油机碳烟排放,结果表明TRF-PAH骨架模型和碳烟模型能重现缸内燃烧和排放的特性.
A new model of TRF-PAH skeleton was constructed by coupling the polycyclic aromatic hydrocarbon (PAH) skeleton model with the toluene reference fuel (TRF) oxidation model. The new TRF-PAH skeleton model was used as the gas-phase chemical reaction model for fuel combustion, Different molecular structure of the fuel oxidation process to generate PAHs and soot also have different research conclusions, this paper further optimized the PAHs as a precursor of soot for carbon soot semi-empirical model.Toluene through the flow reactor, stirred reactor And oxidative / pyrolysis experiments in shock tube showed that the new TRF-PAH framework model can relatively accurately predict the concentration of small molecule PAHs and important intermediate components.By comparing the calculated value of benzene generated in the oxidation of alkanes and aromatic hydrocarbons It can be found that the molecular structure of the fuel has a great influence on the formation pathways of PAHs.In addition, the improved soot model uses the experiment of cracking and oxidation in the shock tube with toluene, n-heptane / toluene and isooctane / toluene mixture as fuel The results show that the simulated value of soot is in good agreement with the experimental data under a wide range of working conditions.Finally, a new soot model is applied to the KIVA program to simulate the diesel engine with TRF20 as fuel Soot emissions, the results show that the TRF-PAH skeleton model and the soot model can reproduce the characteristics of in-cylinder combustion and emissions.