Percussive drilling is suitable for fragmentation of high temperature hard rocks in geothermal wells. In actual geothermal drilling, the heat exchange will occur between the low temperature drilling fluid and the high temperature rocks. This heat transfer effects can cause thermal stress in rocks. High temperature environment and thermal stress will cause rock damage. Therefore, when analyzing percussive drilling based on high temperature rock, the high temperature and heat transfer need to be considered. This article focuses on the effects of mechanical percussion-heat transfer couplings on impact stress wave propagation, energy transfer efficiency and rock damage in percussive drilling. At first, the physical model for mechanical percussion-heat transfer coupled process was built. And then the heat transfer model, fully coupled thermal stress calculation method, temperature-dependent plasticity damage model for rocks, and impact energy transfer model were introduced. Finally, the mechanical percussion-heat transfer coupled process were simulated. The main findings show that the high temperature effect will reduce the impact energy transfer efficiency. However, it can also reduce the rock strength, which contributes to the generation of rock tensile damage in percussive drilling. The heat exchange between low temperature drilling fluid and the high temperature rock will cause the tensile thermal stress in rocks. This tensile thermal stress can induce rock tensile damage, which will improve the impact energy transfer efficiency in percussive drilling. As the control group, the rocks being heated will reduce the energy transfer efficiency in percussion drilling. When the input impact energy (less than 102 J under the present simulation conditions) is small, the impact energy transfer efficiency of stinger teeth is greater than that of hemispherical teeth. And when the input impact energy is large, the impact energy transfer efficiency of hemispherical teeth is greater than that of stinger teeth. The key findings of this study are expected to provide some theoretical guidance for high-efficiency fragmentation of high temperature hard rocks in percussive drilling.

冲击钻井适用于地热井中高温硬岩的破碎。在实际地热钻井中，低温钻井液与高温岩石之间会发生热交换。这种传热效应会在岩石中引起热应力。高温环境和热应力会造成岩石破坏。因此，在分析基于高温岩石的冲击钻进时，需要考虑高温和传热。本文重点介绍机械冲击传热耦合对冲击钻探中冲击应力波传播、能量传递效率和岩石损伤的影响。首先建立了机械冲击传热耦合过程的物理模型。然后是传热模型，介绍了全耦合热应力计算方法、岩石温度相关塑性损伤模型和冲击能量传递模型。最后，对机械冲击传热耦合过程进行了模拟。主要研究结果表明，高温效应会降低冲击能量传递效率。然而，它也会降低岩石强度，这有助于在冲击钻探中产生岩石拉伸损伤。低温钻井液与高温岩石的热交换会在岩石中产生拉伸热应力。这种拉伸热应力会引起岩石拉伸损伤，这将提高冲击钻中的冲击能量传递效率。作为对照组，被加热的岩石会降低冲击钻进的能量传递效率。当输入冲击能量（目前模拟条件下小于102 J）较小时，托管齿的冲击能量传递效率大于半球齿。并且当输入冲击能量较大时，半球形齿的冲击能量传递效率大于托管齿。该研究的主要成果有望为冲击钻进高温硬岩高效破碎提供一定的理论指导。半球形齿的冲击能量传递效率高于托管齿。本研究的主要成果有望为冲击钻进高温硬岩高效破碎提供一定的理论指导。半球形齿的冲击能量传递效率高于托管齿。该研究的主要成果有望为冲击钻进高温硬岩高效破碎提供一定的理论指导。