A large data bank of more than 700 gas-condensate samples collected from literature and experiments was established. On this basis, empirical correlations and equations of state commonly used to calculate dew-point pressure (DPP) were evaluated. A new model for estimating DPP was proposed. All the empirical correlations and the Peng-Robinson state equation were compared, and sensitivity of parameters was analyzed. The current standards used to identify gas condensate were evaluated and found to be not accurate enough. The Peng-Robinson state equation has no unique solution and is affected by multiple factors such as the characterization of C₇₊ components and the splitting scheme. The Nemeth-Kennedy correlation has the highest accuracy when applied to the data bank established in this study, followed by Elsharkawy correlation and Godwin correlation. While Shokir correlation cannot be used for samples without C₇₊ components, it is therefore the lowest in accuracy. The newly proposed model has an average absolute error, root mean square error and coefficient of determination of 7.5%, 588, and 0.87, respectively, and is better than the above four correlations statistically. The proposed model proved to be more accurate and valid when compared to experimental results and simulation with the Peng-Robinson state equation.

建立了从文献和实验中收集的700多个凝析气样品的大型数据库。在此基础上，评估了通常用于计算露点压力（DPP）的经验相关性和状态方程。提出了一种估计DPP的新模型。比较了所有的经验相关性和Peng-Robinson状态方程，并分析了参数的敏感性。对用于鉴定气体冷凝物的当前标准进行了评估，发现不够准确。Peng-Robinson状态方程没有唯一解，并且受多个因素的影响，例如C ₇₊的表征组件和拆分方案。将Nemeth-Kennedy相关性应用于本研究建立的数据库时，其准确性最高，其次是Elsharkawy相关性和Godwin相关性。尽管Shokir相关不能用于没有C ₇₊成分的样品，但是它的准确性最低。新提出的模型的平均绝对误差，均方根误差和确定系数分别为7.5％，588和0.87，并且在统计上优于上述四个相关性。与实验结果和使用Peng-Robinson状态方程进行的仿真相比，该模型被证明更加准确有效。