Spray-induced turbulence proceeding late-injection is regarded to augment mixing, playing a primary role in controlling heat-release rates and pollutant formation in direct-injection engines. This work presents the first application of tomographic PIV (TPIV) to resolve the 3-dimensional, 3-component (3D3C) spray-induced turbulent flow in a spray-guided direct-injection spark-ignition (SG-DISI) engine. TPIV measurements were performed after a single-injection from a hollow-cone spray when particle distributions were suited for accurate particle reconstruction. High-speed PIV (HS-PIV) measurements (4.8 kHz) were combined with phase-locked TPIV measurements (3.3 Hz) to provide the time history of the 2D2C flow-field preceding TPIV. HS-PIV is also used to validate TPIV measurements within the z = 0 mm plane. TPIV uncertainties of 12% are assessed for non-injection operation. TPIV is used to spatially resolve spray-induced turbulent kinetic energy (TKE), shear (S), and vorticity (Ω) distributions. The added 3D3C velocity information is capable of resolving 3D shear layers that produce spatially-coherent 3D turbulent vortical structures, which are anticipated to augment fuel–air mixing. Measurements spatially quantify the increase of these parameters from injection and quantity distributions reveal significant differences to non-injection operation. The isosurface density ($\overline{\rho }$), defined as the volume percentage for which a flow parameter exceeds a given value, is used to identify distributions of the largest TKE, S, and Ω magnitudes. Distributions quantify the increase of TKE, S, and Ω from injection and describe the decay of spray-induced turbulence with time. At $\overline{\rho }$ values below 10%, fuel injection increases TKE, S, and Ω magnitudes in excess of 400% compared to the tumble flow without injection. Magnitudes remained 2-times larger than non-injection operation 16 crank-angle degrees (CADs) after injection. This indicates that spray-induced turbulence enhancement can remain for a significant time after injection. Measurements and analyses provide insight into spray-induced turbulence phenomena and are anticipated to support predictive model development for engine sprays.

喷射引起的湍流进行后期喷射可增强混合，在控制直喷发动机的放热率和污染物形成方面起主要作用。这项工作介绍了层析X射线断层摄影（TPIV）的首次应用，以解决3D，3分量（3D3C）喷雾诱导的直接喷射式火花点火（SG-DISI）发动机中的喷雾诱导的湍流。当粒子分布适合于精确的粒子重建时，从空心锥喷雾器单次注入后进行TPIV测量。高速PIV（HS-PIV）测量（4.8 kHz）与锁相TPIV测量（3.3 Hz）相结合，以提供TPIV之前2D2C流场的时间历史。HS-PIV还用于验证z内的TPIV测量= 0毫米平面。对于非进样操作，TPIV的不确定度为12％。TPIV用于空间解析喷雾引起的湍动能（TKE），切变（S）和涡度（Ω）分布。添加的3D3C速度信息能够解析3D剪切层，这些剪切层会产生空间相干的3D湍流涡旋结构，并有望增强燃料与空气的混合。测量在空间上量化了来自喷射的这些参数的增加，并且数量分布揭示了与非喷射操作之间的显着差异。等值面密度（$\overline{\rho }$）定义为流量参数超过给定值的体积百分比，用于识别最大TKE，S和Ω幅度的分布。分布量化了注入时TKE，S和Ω的增加，并描述了喷雾诱导的湍流随时间的衰减。在$\overline{\rho }$如果值低于10％，则与不喷射的滚流相比，燃油喷射的TKE，S和Ω幅度增加了400％以上。幅度比非注入操作（注入后16个曲柄角度（CAD））大2倍。这表明在注射后，喷雾诱导的湍流增强作用可保持相当长的时间。测量和分析可深入了解喷雾引起的湍流现象，并有望为发动机喷雾的预测模型开发提供支持。