CAJ | 학술논문

为了揭示钻井液在钻柱内的流动特性，采用数值模拟方法建立了涡动钻柱内赫巴流体的流动模型，结合流体力学相关理论，对比分析了速度剖面与表观黏度剖面，研究了钻柱自转速度、公转速度、轴向流速及流体密度等参数的变化对钻柱内流场的影响，得到了各参数对涡动钻柱内摩阻压耗的影响规律。研究表明，公转速度正向增大或反向减小时摩阻压耗都有减小的趋势，自转速度增大时摩阻压耗有增大的趋势。由此可见，考虑钻柱涡动的摩阻压耗变化规律，可使涡动钻柱内钻井液的描述更接近于实际钻井工况，有助于钻井液循环系统的优化。
위료게시찬정액재찬주내적류동특성，채용수치모의방법건립료와동찬주내혁파류체적류동모형，결합류체역학상관이론，대비분석료속도부면여표관점도부면，연구료찬주자전속도、공전속도、축향류속급류체밀도등삼수적변화대찬주내류장적영향，득도료각삼수대와동찬주내마조압모적영향규률。연구표명，공전속도정향증대혹반향감소시마조압모도유감소적추세，자전속도증대시마조압모유증대적추세。유차가견，고필찬주와동적마조압모변화규률，가사와동찬주내찬정액적묘술경접근우실제찬정공황，유조우찬정액순배계통적우화。
In order to reveal flow behavior of drilling fluid in drill string ,numerical simulation method is adopted to establish a mathematical flow model about Herschel-Bulkely fluid in w hirl drill string .Com-bined with the theory of fluid mechanics ,the model was used to analyze and compare velocity and apparent viscosity profiles .The effects of variation in drill string rotation velocity ,revolution velocity ,axial flow ve-locity and fluid density on flow field were examined ,the regularity of effect with each parameter on friction pressure loss in whirl drill string was found .The study shows that friction pressure loss was reduced with the positive increase or reverse decrease of revolution speed ,but friction pressure loss increased with the in-crease of rotation speed .T herefore ,w hen taking friction pressure loss into account ,the description of drill-ing fluid flow in w hirl drill string will be much closer to actual drilling condition ,facilitating the optimiza-tion of drilling circulation system ,it can be of great significance to safe and efficient drilling .