There are some difficult problems in deep and ultra-deep oil and natural gas drilling process due to the complex stress environment and hard formation, such as slow drilling speed, well deviation and high cost. As one of the important parameters to measure rock-breaking efficiency, mathematical model of failure volume is proposed in this paper, which is suitable for deep-well rock-breaking technology. First, the particle jet impact rock-breaking laboratory experiment was conducted based on the self-developed experimental platform, and the strength of rock specimen was tested. Then, the failure volume model of particle jet impact rock-breaking which varied with particle size, and water-jet velocity was established based on contact mechanics. Meanwhile, the simulation model and method of particle jet impact rock was carried out and introduced, and damage evolution was dynamical simulated. Comparative analysis of experiment results, model calculation and dynamic simulation was used to analyze the failure volume, and it showed, failure volume would increase linearly with increase of water-jet velocity, while particle size has little effect on failure volume under the condition of constant nozzle diameter. The comparison results of theoretical modeling and rock-breaking experiment are basically consistent, which proves the correctness and applicability of failure volume model.

由于复杂的应力环境和坚硬的地层，在深，超深石油天然气开采过程中存在一些困难的问题，如钻井速度慢，井眼偏差大，成本高等。作为衡量破岩效率的重要参数之一，提出了适用于深井破岩技术的破坏体积数学模型。首先，在自行开发的实验平台的基础上进行了粒子射流冲击破岩实验室实验，并对岩石试样的强度进行了测试。然后，基于接触力学，建立了随粒径变化而变化的射流冲击碎石破坏体积模型，并建立了射流速度。同时，介绍并介绍了颗粒射流冲击岩石的模拟模型和方法，并动态模拟了损伤演化。通过对实验结果，模型计算和动态仿真的对比分析，对破坏量进行了分析，结果表明，随着水射流速度的增加，破坏量将线性增加，而在恒定条件下，粒径对破坏量的影响很小。喷嘴直径。理论模型与破岩实验的比较结果基本一致，证明了破坏体积模型的正确性和适用性。在恒定的喷嘴直径条件下，粒径对失效体积影响很小。理论模型与破岩实验的比较结果基本一致，证明了破坏体积模型的正确性和适用性。在恒定的喷嘴直径条件下，粒径对失效体积影响很小。理论模型与破岩实验的比较结果基本一致，证明了破坏体积模型的正确性和适用性。