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井筒内液体温度主要受井筒向周围地层的热损耗速度的影响。此外,它还与液体所在位置深度、生产或注入时间等影响因素有关。本文提出了一种新的估算井筒两相稳定流动时液体温度的模型,该模型使用了本文第一部分热扩散方程的解,并且考虑了对流和热传导对井筒液体温度的影响。模型中有关井筒两相流的流动规律的描述是采用汉森(HaSan)和卡波尔(Kabir)模型。此外,本文的计算实例展示了井筒液体温度分布计算的全过程,计算结果表明油套环空介质的对流作用对井筒液体温度的影响是十分严重的。在过去,由于绝大多数模型在估算井筒液体温度随深度变化方面的作用的局限性,结果造成用户在求井筒液体温度时多采用井底温度和井口温度的线性插值。井口温度的实测值和预测值间存在的较大差异的事实说明井筒液体温度分布不是线性的。研究结果还发现由于存在焦尔-汤普森(Joule-Thompson)效应,自由气体的增加会导致井口温度下降,因而雷米(Ramey)提出的单相流井筒温度计算式不适宜于两相流。为此,本文提出一个两相流井筒温度计算式。
The fluid temperature in the wellbore is mainly affected by the rate of heat loss from the wellbore to the surrounding formation. In addition, it is also related to the depth of the location of the liquid, the production or injection time and other influencing factors. In this paper, we propose a new model to estimate the temperature of liquid in steady-state two-phase wellbore. The model uses the solution of the first part of the thermal diffusion equation and considers the influence of convection and heat conduction on the liquid temperature in wellbore. The model’s description of the wellbore flow pattern is based on the HaSan and Kabir models. In addition, the calculation example in this paper shows the whole process of calculating the temperature distribution of wellbore fluid. The calculation results show that the convection effect of annulus medium on the wellbore liquid temperature is very serious. In the past, due to the limitations of the vast majority of models in estimating borehole fluid temperature changes with depth, the user was forced to use linear interpolation of bottom hole temperature and wellhead temperature when seeking borehole fluid temperatures. The fact that there is a large difference between the measured and predicted wellhead temperatures indicates that the wellbore liquid temperature distribution is not linear. The results also show that due to the Joule-Thompson effect, an increase in free gas leads to a decrease in the wellhead temperature, so the single-phase wellbore temperature formula proposed by Ramey is not suitable for two-phase flow. To this end, this paper presents a two-phase wellbore temperature formula.