Turbulent hot-jet ignition (THJI) is an advanced ignition enhancement technology which can potentially overcome the problem associated with lean burn combustion. The present study makes an effort on the comprehensive understanding of a hydrogen fueled THJI chamber with various pre-chamber spark locations. Computational fluid dynamics (CFD) simulations are performed using an in-house code based on the KIVA-3V release 2 program coupled with an in-house chemical solver. A detailed chemical kinetics mechanism with 10 species and 19 reversible reactions is used for the H₂/air mixture in both the pre-chamber and the main chamber. The results show that moving the spark ignition location farther from the orifice significantly reduces the $0-10\text{\%}$ mass fraction burn period. By analyzing the local Mach number, turbulence kinetic energy and turbulence length scale, the compressibility and turbulence level of the jet flow are evaluated. Further analysis of the OH mass fraction distribution identifies three regions in the hot jet, i.e. extinction region, just-igniting region and combustion region. A critical Damköhler number of 0.3 is determined to separate the extinction region from the other regions. Meanwhile, transition Damköhler numbers ranging from 0.3 to 0.6 are determined in the just-igniting region.

湍流热喷射点火（THJI）是一项先进的点火增强技术，可以潜在地克服与稀薄燃烧相关的问题。本研究致力于全面了解带有各种预燃室火花位置的氢燃料THJI燃烧室。使用基于KIVA-3V版本2程序并结合内部化学求解器的内部代码执行计算流体动力学（CFD）模拟。在前室和主室中，H ₂ /空气混合物均采用了具有10种物质和19个可逆反应的详细化学动力学机理。结果表明，将火花点火位置移动到距孔口更远的位置可显着降低$0-10\text{％}$质量分数燃烧期。通过分析局部马赫数，湍流动能和湍流长度尺度，评估了射流的可压缩性和湍流水平。OH质量分数分布的进一步分析确定了热射流中的三个区域，即熄灭区域，正点火区域和燃烧区域。确定临界Damköhler数为0.3，以将灭绝区域与其他区域区分开。同时，在刚点火区域内确定了从0.3到0.6的过渡Damköhler数。