CAJ | 학술논문

本文基于井筒与地层间能量平衡原理,将井筒钻井液划分成不同径向单元网格,建立了考虑径向温度梯度条件下钻井液层间温度模型;同时引入钻井液轴向导热项,建立了钻井液轴向导热温度模型,将数学模型应用隐式有限差分法离散与求解.计算结果表明:钻井液径向温度梯度对井筒径向与轴向温度产生的误差分别为0.15?C和0.2?C左右;而钻井液轴向导热对井筒温度分布几乎不产生影响.因此,通过建立的数学模型进行系统分析表明,在建立井筒-地层耦合瞬态传热模型时可忽略两者对井筒温度分布的影响.基于数学建模方法验证了以前学者模型假设条件的正确性,为油气井与地热井井下温度分布规律深入研究奠定了可靠的理论基础.
본문기우정통여지층간능량평형원리,장정통찬정액화분성불동경향단원망격,건립료고필경향온도제도조건하찬정액층간온도모형;동시인입찬정액축향도열항,건립료찬정액축향도열온도모형,장수학모형응용은식유한차분법리산여구해.계산결과표명:찬정액경향온도제도대정통경향여축향온도산생적오차분별위0.15?C화0.2?C좌우;이찬정액축향도열대정통온도분포궤호불산생영향.인차,통과건립적수학모형진행계통분석표명,재건립정통-지층우합순태전열모형시가홀략량자대정통온도분포적영향.기우수학건모방법험증료이전학자모형가설조건적정학성,위유기정여지열정정하온도분포규률심입연구전정료가고적이론기출.
Therefore, in this study, based on energy balance principle between wellbore and formation, a temperature model of drilling fluid layers was established under different grid units of wellbore condition. Meanwhile, the axial thermal conductivity temperature model of drilling fluid was established by introducing axial conduction items of drilling fluid, followed by using discrete and solving of implicit finite difference method to these mathematical models. The calculation results indicated that the error temperature of the radial and axial of drilling fluid wellbore temperature which was caused of radial temperature gradient were 0.15 and 0.2 ?C respectively, whereas axis thermal conductivity of drilling fluid has little effect on wellbore temperature distribution. Therefore, the above results confirmed that it can ignore both of them to influence wellbore temperature distribution by established the wellbore-formation coupled transient heat transfer model. Moreover, it is the first proved the correctness of model assumptions from previous scholars based on the mathematical modeling methods, and then further provides the reliable theoretical basis for down-hole temperature distribution of oil and gas well and geothermal well.