试井分析中的离散数据拉普拉斯变换方法

LAPLACE TRANSFORM METHOD OF DISCRETE DATA IN WELL TEST ANALYSIS

随着计算机技术和试井分析理论的日益发展 ,人们将拉普拉斯数值变换方法引入到试井分析中 ,并得到越来越广泛的应用 ,拉普拉斯变换已经成为处理试井测试数据的一种重要手段。以前人们研究较多的是基于连续函数的拉普拉斯变换方法 ,然而 ,试井测试所获得的数据通常都是某一时间区间上受到一定测试噪声影响的有序离散数据点列 ,所以 ,以前的那些方法不能直接用于处理试井测试数据。为此 ,文章在考虑试井测试数据特点和拉普拉斯变换对原函数要求的基础上 ,通过将整个半无穷界时间域分成三段 ,对每个时间段分别采取合适的离散数据积分算法 ,推导建立了适用于试井分析的离散数据拉普拉斯变换方法。该方法具有方便快捷、计算过程简单、计算稳定可靠的特点 。

As computer technology and well test analysis theory progress rapidly day after gay, Laplace transform method is introduced to well test analysis and applied more and more. Laplace transform has become a major tool for well test data processing. In the past, Laplace transform method was applied usually for continuous function. But the data obtained by well test are an ordered discrete data array which are acquired in a period and influenced by testing noise. So, the original method can't be applied directly to process the well test data. According to the characteristics of the well test data and the requirements of Lapace transform to the source function, the article divides the time domain with semi-infinite boundary into 3 sections, applies suitable integral algorithm of discrete data for each time section separately, and derives Laplace transform method of discrete data which is applicable to the well test analysis. The method has the characteristics of convenience and calculating simple, stable and reliable. It is specially suitable to process the data in computer.