摘要
目前国内各油田开发逐步进入中后期,高气液比油井举升问题日益突显,长柱塞防气泵在原有泵筒外设计排气结构,使进泵气体由此返回环空,达到防止气锁和提高泵效的目的.然而,由于适用界限未知,且缺少经济高效的评价手段,限制了其推广应用.采用CFD方法,引入动网格技术,基于控制方程和波动方程,建立长柱塞防气泵泵筒内气液瞬态流动和泵阀运动规律数值模型;开展室内可视化试验,验证了建立数值模型的准确性,模型平均误差为5.84％;基于数值模型,模拟分析了长柱塞防气泵上、下冲程泵筒内部气液两相流动规律,以及冲程、冲次对泵效率的影响,明确了其适用的气液比范围,当气液比大于400 m3/m3时,长柱塞防气泵泵效低于经济泵效.
Abstract
In China's mid to late stages of oilfield development,the issue of lifting high gas-liquid ratio oil wells has become increasingly prominent.To address this,the long plug gas pump was designed with an exhaust structure outside the original pump barrel.This allows the gas entering the pump to return to the annulus,achieving the goal of improving pump efficiency.However,the applicability of long column plug gas pumps remains unknown due to a lack of cost-effective evaluation methods.To address this issue,we adopted the CFD method and introduced dynamic grid technology.We established a numerical model of gas-liquid transient flow and pump valve motion law in the long column plug anti gas pump barrel based on control equations and wave equations.The purpose of the indoor visualization experiments was to verify the accuracy of es-tablishing numerical models.The average model error was found to be 5.84％.A numerical mod-el was used to simulate and analyze the gas-liquid two-phase flow pattern inside the upper and lower stroke pump barrel of a long column plug gas pump.The impact of stroke and stroke on pump efficiency was also analyzed.The applicable gas-liquid ratio range was determined.When the gas-liquid ratio exceeds 400 m3/m3,the pump efficiency of the long column plug gas pump decreases below the economic pump efficiency.
基金项目
国家科技重大专项(2016ZX05053-015)
NETL
NSTL
万方数据