SEUIF97 This is the C implementation of the high-speed IAPWS-IF97 package seuif97. It is suitable for computation-intensive calculations,such as heat cycle calculations, simulations of non-stationary processes, real-time process monitoring and optimizations. Through the high-speed library, the results of the IAPWS-IF97 are accurately produced several times faster than repeated squaring method and math.pow() of the C standard library. In addition to the source code, the repository provides the compiled shared libraries using GCC and the interfaces to multiple programming languages. The shared libraries Windows(x86/64): libseuif97.dll Linux(x64): libseuif97.so The API for the programming languages Python, C/C++, Excel VBA, C#, Java,MATLAB,Fortran, Rust, Modelica, Pascal Publications 王培红,贾俊颖,程懋华. 水和水蒸汽热力性质IAPWS-IF97公式的通用计算模型[J]. 动力工程,2001,21(6):1564-1567 [ pdf ] 芮嘉敏,孙振业,程懋华. 基于最短加法链状态空间树的IAPWS-IF97快速计算方法[J]. 汽轮机技术,2017,59(4):245-247 [ pdf ] Functions of the SEUIF97 Shared Library Functions of water and steam propertiesand the thermodynamic process of steam turbine are provided in SEUIF97 Water and Steam Properties Using SEUIF97, you can set the state of steam using various pairs of know properties to get any output properties you wish to know, including in the 30 properties in libseuif97. The following 12 input pairs are implemented: (p,t) (p,h) (p,s) (p,v) (t,h) (t,s) (t,v) (p,x) (t,x) (h,x) (s,x) (h,s) Thermodynamic Process of Steam Turbine 1 Isentropic Enthalpy Drop:seuishd(pi,ti,pe) pi - double, inlet pressure(MPa); ti - double, inlet temperature(°C) pe - double, outlet pressure(MPa) 2 Isentropic Efficiency(0~100): seuief(pi,ti,pe,te) (superheated steam zone) pi - double, inlet pressure(MPa); ti - double, inlet temperature(°C) pe - double, outlet pressure(MPa); te - double, outlet temperature(°C) The API C/C++: seuif97.h Python: seuif97.py Excel VBA: seuif97.bas C#: seuif97.cs Java: seuif97.java MATLAB: seuif97.m Rust: seuif97.rs Fortran: seuif97.f08 Modelica: seuif97.mo Pascal: seuif97.pas Install SEUIF97 Use the shared library from one programming language, you may Put the shared library in the default Lib path of OS or the programming language Windows(x86/64) copy libseuif97.dll in the Windows/x86 or Windows/x64 folder to a default path of Windows32/64's DLL: C:\Windows\System Linux(x64) copy libseuif97.so in the Linux/x64 folder to a default path of Linux shared lib : /usr/lib/ Add the API file of the programming language to its API path The API paths of different programming languages are different,please refer to the Examples of different programming languages Examples The examples using the shared library C/C++ Python Excel VBA(32/64) C# Java Rust MATLAB64 Fortran Modelica Pascal The Function Prototypes in C If you need to modify the APIs provided in the repository or program your own APIs, you can refer to the library's header file: seuif97.h. // Functions of Properties double seupt(double p, double t, int propertyID); double seuph(double p, double h, int propertyID); double seups(double p, double s, int propertyID); double seupv(double p, double v, int propertyID); double seuth(double t, double h, int propertyID); double seuts(double t, double s, int propertyID); double seutv(double t, double v, int propertyID); double seuhs(double h, double s, int propertyID); double seupx(double p, double x, int propertyID); double seutx(double t, double x, int propertyID); double seuhx(double h, double x, int propertyID); double seusx(double s, double x, int propertyID); //The Functions for Thermodynamic Process of Steam Turbine double seuishd(double pi, double ti, double pe); double seuief(double pi, double ti, double pe, double te); Properties Propertry Unit Symbol propertryID Pressure MPa p 0 Temperature °C t 1 Density kg/m^3 ρ 2 Specific Volume m^3/kg v 3 Specific enthalpy kJ/kg h 4 Specific entropy kJ/(kg·K) s 5 Specific exergy kJ/kg e 6 Specific internal energy kJ/kg u 7 Specific isobaric heat capacity kJ/(kg·K) cp 8 Specific isochoric heat capacity kJ/(kg·K) cv 9 Speed of sound m/s w 10 Isentropic exponent k 11 Specific Helmholtz free energy kJ/kg f 12 Specific Gibbs free energy kJ/kg g 13 Compressibility factor z 14 Steam quality x 15 Region r 16 Isobaric cubic expansion coefficient 1/K ɑv 17 Isothermal compressibility 1/MPa kT 18 Partial derivative (∂V/∂T)p m3/(kg·K) (∂V/∂T)p 19 Partial derivative (∂V/∂P)T m3/(kg·MPa) (∂V/∂P)T 20 Partial derivative (∂p/∂t)v MPa/K (∂p/∂t)v 21 Isothermal throttling coefficient kJ/(kg·MPa) δt 22 Joule-Thomson coefficient K/MPa μ 23 Dynamic viscosity kg/(m·s) η 24 Kinematic viscosity m^2/s ν 25 Thermal conductivity W/(m.K) λ 26 Thermal diffusivity um^2/s a 27 Prandtl number Pr 28 Surface tension mN/m σ 29