全尺寸射孔完井水平井筒流动压降实验

采用外径139.7 mm的壁面打孔套管模拟射孔完井水平井筒,通过模拟实验研究射孔参数及壁面注入比对各种压降的影响规律。实验结果表明:①随着射孔密度、射孔孔径、射孔相位的增大,壁面摩擦压降和总压降均增大,混合压降减小。②射孔套管出口主流雷诺数相同时,随着壁面注入比的增大,总压降和混合压降均增大。壁面注入比小于临界值(本研究条件下为0.05%～0.10%)时,混合压降小于零;壁面注入比大于临界值时,混合压降大于零。壁面注入比小于0.10%时,加速度压降可以忽略;壁面注入比大于0.10%时,加速度压降随壁面注入比的增大而显著增加。③随着壁面注入比的增大,壁面摩擦压降占总压降的比例逐渐减小,加速度压降占总压降的比例逐渐增大。壁面注入比小于1.00%时,混合压降占总压降的比例随壁面注入比的增大而增大;壁面注入比大于1.00%时,混合压降占总压降的比例基本保持不变。

Experiment of complex flow in full size horizontal wells with perforated completion

A full size perforated casing of 139.7 mm in external diameter was adopted to simulate the horizontal wellbore. The influences of perforation parameters and injection rate on the pressure drop in horizontal wells are investigated by experiments. The results show that: (1) With the increase of perforation density, perforation diameter and perforation phase, both the frictional pressure drop and the total pressure drop increase and the mixture pressure drop decreases. (2) When the mainstream Reynolds number at the perforated casing exit remains constant, with the increase of injection rate, the total pressure drop and mixing pressure drop increase. When the injection rate is less than the critical injection rate (0.05%-0.10% under the study conditions), the mixing pressure drop is less than 0. When the injection rate is greater than the critical injection rate, the mixing pressure drop is greater than 0. The acceleration pressure drop can be neglected when the injection rate is less than 0.10%, otherwise the acceleration pressure drop rises significantly with the increase of injection rate. (3) With the increase of injection rate, the proportion of frictional pressure drop to total pressure drop decreases while that of acceleration pressure drop to total pressure drop increases. When the injection rate is less than 1.00%, the proportion of mixing pressure drop to total pressure drop tends to rise with the increase of injection rate. When the injection rate is greater than 1.00%, the proportion of mixing pressure drop to total pressure drop almost remains unchanged.