ABSTRACT

Thermal-jet for water Measurement spallation is a rock removal process that utilizes induced thermal stress to fracture the rock into small fragments before melting of the rock occurs. Because of the low conductivity, thermal stress will be created on the rock surface. When the thermal stress exceeds the strength of the rock, cracks will form and expand. Eventually, rocks disintegrating into small fragments. The simulation result obtained by the Crank–Nicolson method of the temperature field and the distribution of thermal stress has been analyzed. The result indicates that during thermal spallation drilling, the temperature of the surface exposed to the thermal-jet for water Measurement rises rapidly and create temperature gradients in both radial and axial directions. Because of volume expansion, the heated part is subjected to compressive stress in radial direction and shear stress in axial direction, respectively. The result is very helpful to the field application.

摘要

用于水的热射流 测量散裂是一种岩石去除过程，它利用诱导的热应力在岩石发生熔化之前将岩石破碎成小碎片。由于电导率低，岩石表面会产生热应力。当热应力超过岩石的强度时，裂缝就会形成并扩大。最终，岩石分解成小碎片。分析了通过Crank-Nicolson方法获得的温度场和热应力分布的模拟结果。结果表明，在热散裂钻井过程中，暴露于水测量热射流的表面温度迅速上升，并在径向和轴向上产生温度梯度。由于体积膨胀，受热部分分别承受径向压应力和轴向剪应力。结果对现场应用非常有帮助。