应用VB实现AGA8-92DC气体压缩因子计算方法

天然气压缩因子在天然气工程计算中具有重要的地位,其计算方法有多种,其中就包括由美国燃气协会提出的基于气体组成来计算压缩因子的AGA8-92DC方程。根据GB/T 17747.2-2011标准所给出的AGA8-92DC方法计算过程,用Visual Basic6.0 program编写了计算程序。为了验证程序的正确性,分别将程序计算值与GB/T 17747.2标准提供的计算值和含碳贫气气样实测值进行了对比,且获得了较小的计算误差。由计算值与实测值的对比结果可知,通过Visual Basic6.0 program所编写的AGA8-92DC方法计算程序而得到的计算结果能够满足工程上的要求;对于中高压含碳贫气,AGA8-92DC方法具有较高的计算准确度;当气体温度升高时,AGA8-92DC方法的计算误差将有所减小。

Calculation of Gas Compressibility Factor by AGA8-92DC Equation Compiled by VB

Natural gas compressibility factor plays an important role in the natural gas engineering calculations and its calculation methods has many kinds, including AGA8-92DC equation of the gas compressibility factor using gas composition proposed by the American Gas Association. In this paper, according to the calculation process of AGA8-92DC equation described by GB/T17747.2-2011 standard, Visual Basic6.0 program was used to compile the computing program. In order to verify the correctness of the program, the calculated values of the program with the calculated values of GB/T 17747.2 standard and the measured values of lean-gas with carbon dioxide were respectively compared, and the smaller calculation error was obtained. The comparison between the calculated values and the measured values shows that, at first the calculation results obtained from the calculating program of AGA8-92DC method based on Visual Basic6.0 program can meet the engineering requirements. Secondly, for the medium-pressure or high-pressure lean-gas with carbon dioxide, AGA8-92DC method has higher calculation accuracy. Thirdly, when the gas temperature increases, the calculation error of AGA8-92DC method will reduce.