The NIST REFPROP software program is a powerful tool for calculating thermophysical properties of industrially important fluids, and this manuscript describes the models implemented in, and features of, this software. REFPROP implements the most accurate models available for selected pure fluids and their mixtures that are valid over the entire fluid range including gas, liquid, and supercritical states, with the goal of uncertainties approaching the level of the underlying experimental data. The equations of state for thermodynamic properties are primarily of the Helmholtz energy form; a variety of models are implemented for the transport properties. We document the models for the 147 fluids included in the current version. A graphical user interface generates tables and provides extensive plotting capabilities. Properties can also be accessed through third-party apps or user-written code via the core property subroutines compiled into a shared library. REFPROP disseminates international standards in both the natural gas and refrigeration industries, as well as standards for water/steam.

中文翻译：

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NIST REFPROP 数据库，用于工业重要流体的高精度特性

NIST REFPROP 软件程序是计算工业上重要流体的热物理性质的强大工具，本手稿描述了该软件中实现的模型和功能。REFPROP 为选定的纯流体及其混合物实施了最准确的模型，这些模型在包​​括气体、液体和超临界状态在内的整个流体范围内都有效，其目标是使不确定性接近基础实验数据的水平。热力学性质的状态方程主要是亥姆霍兹能量形式；为传输属性实现了多种模型。我们记录了当前版本中包含的 147 种流体的模型。图形用户界面生成表格并提供广泛的绘图功能。也可以通过第三方应用程序或用户编写的代码通过编译到共享库中的核心属性子例程来访问属性。REFPROP 传播天然气和制冷行业的国际标准，以及水/蒸汽标准。