井下循环温度模型及其敏感性分析

准确的井下循环温度对钻井与完井工程十分重要。在前人的基础上，根据热力学第一定律及传热学基本原理，建立了井内液体与井筒之间热交换的二维瞬态循环温度的数学模型，用无条件稳定的全隐式有限差分法数值求解数学模型，将所建立模型的预测结果与有关模型进行比较，并对影响井下循环温度的参数进行敏感性分析。该模型可用于计算实际循环条件下和管内液体、管壁、环空液体与地层的温度分布。

A Wellbore Temperature Model & Its' Parametric Sensitivity Analysis

It is important for the drilling and completion to learn about accurate distribution of circulating temperature in the wellbore. According to the first law of thermodynamics and the theorems of heat transfer, a new two dimension transient mathematical model of circulating temperature of heat exchange between the liquid in wellbore, pipe string and underground formation has been proposed, which has been solved by termless steady finite difference method. The predicted results from the new model presented in this paper are satisfactorily close to those from other proven models. The sensitivities of parameters to affect the circulating temperature in wellbore have also been analyzed. The new model can be employed to calculate temperature distribution of drilling mud, pipe string, fluid in the annular and the formation of real circulating circumstance.