When simulating fuel sprays in gasoline direct injection (GDI) engines, few studies have investigated resolving the counterbore and how this may influence spray predictions. In this work, we used the stochastic blob and bubble (VSB2) spray model to conduct simulations where fuel was injected into a constant volume combustion vessel. The counterbore was resolved both radially and axially. In addition, the injector orifice was resolved into nine cells. The boundary conditions were the same as the engine combustion network (ECN) noncombusting case for multicomponent Spray G (G1, E00 case in ECN, Spray G). Results obtained using two simulation meshes were compared to experimental data: (1) without resolving the counterbore and (2) with resolved counterbore. Both meshes predicted the experimental liquid and vapor penetration lengths reasonably well and the differences in the penetration lengths between the two meshes were insignificant. However, a clear difference was detected in the fuel-air mixing (quantified by the mixing rate) and maximum values of к and ε. There were also noticeable differences between the two meshes in the peak fuel vapor fractions of the two most volatile components.

中文翻译：

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汽油直喷发动机工况多组分燃油喷射模型验证及对沉孔喷油器解决影响的研究

在模拟汽油直喷 (GDI) 发动机中的燃油喷雾时，很少有研究研究解决沉孔以及这可能如何影响喷雾预测。在这项工作中，我们使用随机斑点和气泡 (VSB2) 喷雾模型进行模拟，其中将燃料喷射到恒定体积的燃烧容器中。沉孔在径向和轴向上均已解析。此外，注射器孔被分解成九个单元。边界条件与多组分喷雾 G 的发动机燃烧网络 (ECN) 非燃烧情况相同（ECN 中的 G1，E00 情况，喷雾 G）。将使用两个模拟网格获得的结果与实验数据进行了比较：(1) 不解析沉孔和 (2) 解析沉孔。两种网格都可以很好地预测实验液体和蒸汽的穿透长度，并且两种网格之间的穿透长度差异不显着。然而，在燃料-空气混合（由混合率量化）和 к 和 ε 的最大值中检测到明显的差异。在两个最易挥发组分的峰值燃料蒸气分数中，两个网格之间也存在显着差异。