负压采油过程中泵吸入口处压差的计算方法

A METHOD OF CALCULATING PRESSURE DROP AT THE INLET OF PUMP DURING NEGATIVE PRESSURE PRODUCTION

负压采油技术是采油工程中用以增加产量的一种有效手段；负压采油的实质是采用一定的技术措施在泵入口处造成水击，即在充满液体的管道系统进行快速泄压，当压力急剧下降时，在短时间内可以在泵入口处形成负压。在负压采油过程中，如何计算瞬间形成的负压值的大小，是分析、评价负压采油效果和进行产能预测的理论依据，也是采油工作者急待解决的问题之一。本文利用流体力学的基本原理，从负压采油的实际出发，给出了负压采油过程所遵循的基本方程，并对其进行求解，推导出了负压采油过程中泵吸入口处压差的理论计算公式。结合辽河油田某井的生产实际，得出了瞬间在泵吸入口处形成的负压，其计算结果可以指导现场负压采油方案设计和产能预测。

Negative pressure production is an effective technology used in oil production engineering to increase productivity.The essence of negative pressure production technology is to induce a negative pressure at the inlet of a pump through rapid dischage within the fully filled tubular system.To calculae the value of negative pressure during negative oil production proccss,is on the theoretical basis of productivity prediction,production effectiveness analysis and evaluation:it is also an important problem that needs urgent solution for oil production engineers.In this paper,on the basis of the principlc of fluid mechanics and the practical situation of negative pressure production in the oil field,the basic equations describing the proccss of negative pressure production are given and solved.The formulae calculating pressure drop at the inlet of pump is developed. Combing with the specific well data in Liaohe oil field,the negative pressure formed instantaneously at the inlet of the prmp is calculated.So the results can be rsed to direct the design and the productivity prediction of negative pressure production engineering in the oil field.