激光破岩的理论分析与数值模拟

激光破岩技术在石油工业上具有广阔的应用前景,但目前国内对激光与岩石相互作用机制的研究还比较少见.根据非定常传热学原理分析了均匀激光光束和高斯激光光束照射砂岩时的温度场分布;根据热应力方程和边界条件模拟了砂岩内部的热应力分布,得到有效切削砂岩所需的激光功率阈值;根据能量守恒定律建立岩石的熔化和气化模型,得到一定激光功率下岩石熔化和气化的速率.模拟结果表明,在深井中采用激光钻井技术,其钻进速度远高于常规的机械旋转钻井技术,具有显著的工业应用潜力.

Theoretical Analysis and Numerical Simulation of Laser to Rock

The technology of laser drilling rock has wide applied future in petroleum industry,but there are few mechanism researches of laser to rock interiorly.This thesis analyzed the temperature distribution of the sandstone under the laser with uniform and Gaussian intensity according to the instability heat transfer theory,then simulated the heat stress distribution and the minimum laser intensity to drill sandstone according to the stress equation and boundary condition.The fusion and gasification model was constructed according to the law of conservation of energy and the fusion and gasification speed at certain laser power was calculated.The simulation results show that the speed of laser drilling rock is much faster than mechanical revolving aiguilles technology in deep oil well and has prominent industrial application potential.