欠平衡钻井水平环空两相流对流传热系数实验研究

Experimental study on heat transfer coefficient of two-phase flow of horizontal annulus
for underbalanced drilling

 张楠¹ 冯松林² 毕雪亮¹ 陈勋¹ 于晓文¹ 刘珊珊¹

东北石油大学提高油气采收率教育部重点实验室，黑龙江 大庆 163318 中国石油长庆油田分公司第六采油厂，陕西 榆林 719000

MOE Key Laboratory of Enhanced Oil Recovery, Northeast Petroleum University, Daqing 163318, China No.6 Oil Production Plant, Changqing Oilfield Company, PetroChina, Yulin 719000, China

欠平衡钻井流体一般是气液两相混合流体，温度是欠平衡钻井井底压力控制的重要影响因素之一，研究两相流对流传热对准确预测欠平衡钻井环空温度有重要意义。前人对气液两相流对流传热进行了不少实验研究，但他们的实验都是研究管内流动，且管径较小（20~35 mm），这与欠平衡钻井所处的实际条件有很大的出入。文中进行了大管径水平环空气液两相流对流传热实验研究，分别改变气相流量、液相流量得出不同气、液雷诺数下的环空两相流对流传热系数。分析数据可以得出，气体雷诺数对偏心环空两相流对流传热系数的影响不大，但液体雷诺数是影响该对流传热系数的主要因素。又通过与相同流量下小管径（25.4 mm）、管内流动的气液两相流对流传热系数（Kim实验数据）进行对比得出，在气液雷诺数一致的条件下，气液雷诺数对两相流对流传热系数影响趋势基本一致，但文中实验所测得的对流传热系数小于Kim所测得的实验结果。该实验研究结果对欠平衡钻井井底压力的控制有着重要的指导意义。

 Underbalanced drilling fluid is generally a two-phase mixture of gas-liquid. Temperature is one of the important affecting factors for bottom-hole pressure control during underbalanced drilling; therefore the study of convective heat transfer of two-phase flow is significant to accurately predict annulus temperature of underbalanced drilling. Predecessors have done some experimental studies on convective heat transfer of two-phase mixture of gas-liquid, but their experiments are based on pipe flow and small pipe diameter(20￣35 mm), which is very different from actual conditions of underbalanced drilling. This paper discusses gas-liquid two-phase convective heat transfer with large diameter and horizontal annulus, the different convective heat transfer coefficients of eccentric annulus can be obtained by respectively changing gas flow rate and liquid flow rate. The conclusion is that gas Reynolds number has little effect on heat transfer coefficient of two-phase of eccentric annulus, however, liquid Reynolds number is the main effecting factor; experimental data of this study are smaller than those measured by Kim under the same gas or liquid Reynolds number, however they have the same trend. The results of experiment have important directive significance to bottom hole pressure control of underbalanced drilling.

10.6056/dkyqt201601028