Jet breaking using a high‐pressure nozzle is one solution for breaking natural gas hydrate (NGH) formations, creating a larger breaking volume and fluidizing broken solid fragments. Based on the analysis of various jet breaking mechanisms for the variation of the flow velocity of the internal and outlet sections of different nozzles, a straight‐swirling mixed nozzle (SSMN) was designed. We obtained different jet breaking effects for a single nozzle, including the influences of the working pressure and target distance on the hole shape, as well as working pressure on hole parameters and target distance on hole parameters. In addition, we analyzed the influences of the nozzle number, type of NGH rock, and construction parameters on the rock‐breaking efficiency and selected the best combination mode of multiple nozzles. The research results of the rock‐breaking mechanism and efficiency of the SSMN promotes the development of commercial mining technology for nondiagenetic NGH in deep‐sea shallow areas.

中文翻译：

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深海浅层非成岩天然气水合物直旋混合喷嘴的破岩机理与效率

使用高压喷嘴的射流破碎是一种破碎天然气水合物（NGH）地层，产生更大破碎体积并流化破碎固体碎片的解决方案。基于对不同喷嘴内部和出口部分流速变化的各种射流破碎机理的分析，设计了直旋混合喷嘴（SSMN）。我们对单个喷嘴获得了不同的喷射破坏效果，包括工作压力和目标距离对孔形状的影响，以及工作压力对孔参数和目标距离对孔参数的影响。此外，我们分析了喷嘴数量，NGH岩石类型和施工参数对破碎效率的影响，并选择了多个喷嘴的最佳组合方式。