Biodiesel and blends with petroleum diesel are promising renewable alternative fuels for engines. In the present study, the soot concentration generated from four biodiesels, two pure methyl esters, and their blends with petroleum diesel are measured in a series of fully pre-vapourised co-flow diffusion flames. The experimental measurements are conducted using planar laser induced-incandescence (LII) and laser extinction optical methods. The results show that the maximum local soot volume fractions of neat biodiesels are 24.4% - 41.2% of pure diesel, whereas the mean soot volume fraction of neat biodiesel cases was measured as 11.3% - 21.3% of pure diesel. The addition of biodiesel to diesel not only reduces the number of inception particles, but also inhibits their surface growth. The discretised population balance modelling of a complete set of soot processes is employed to compute the 2D soot volume fraction and size distribution across the tested flames. The results show that the model also demonstrates a reduction of both soot volume fraction and primary particle size by adding biodiesel fuels. However, it is not possible to clearly determine which factors are responsible for the reduction from the comparison alone. Moreover, analysis of the discrepancies between numerical and experimental results for diesel and low-blending cases offers an insight for the refinement of soot formation modelling of combustion with large-molecule fuels.

生物柴油及其与石油柴油的混合物是有前途的可再生发动机替代燃料。在本研究中，在一系列完全预汽化的同流扩散火焰中测量了由四种生物柴油，两种纯甲酯及其与石油柴油的混合物产生的烟灰浓度。使用平面激光诱导发光（LII）和激光消光光学方法进行实验测量。结果表明，纯生物柴油的最大局部烟灰体积分数为纯柴油的24.4％-41.2％，而纯生物柴油案例的平均烟灰体积分数为纯柴油的11.3％-21.3％。向柴油中添加生物柴油不仅减少了起始颗粒的数量，而且抑制了其表面生长。一套完整的烟灰过程的离散化人口平衡模型用于计算二维烟灰体积分数和整个测试火焰的尺寸分布。结果表明，该模型还证明了通过添加生物柴油燃料，烟灰体积分数和一次粒径均降低。但是，仅凭比较不可能明确确定哪些因素导致了减少。此外，对柴油和低掺和情况下数值与实验结果之间差异的分析为精炼大分子燃料燃烧的烟灰形成模型提供了见识。结果表明，该模型还证明了通过添加生物柴油燃料，烟灰体积分数和一次粒径均降低。但是，仅凭比较不可能明确确定哪些因素导致了减少。此外，对柴油和低掺和情况下数值与实验结果之间差异的分析为精炼大分子燃料燃烧的烟灰形成模型提供了见识。结果表明，该模型还证明了通过添加生物柴油燃料，烟灰体积分数和一次粒径均降低。但是，仅凭比较不可能明确确定哪些因素导致了减少。此外，对柴油和低掺和情况下数值与实验结果之间差异的分析为精炼大分子燃料燃烧的烟灰形成模型提供了见识。