SEUIF97
 [](https://github.com/thermalogic/RustSEUIF97/actions/workflows/rust.yml)
This is the Rust implementation of the high-speed IAPWS-IF97 package **seuif97** with C and Python binding. 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 package, the results of the IAPWS-IF97 are accurately produced at about 5-20x speed-up compared to using the `powi()` of the Rust standard library in the `for`loop directly when computing the basic equations of Region 1,2,3.
**The Fast Methods**
1. The multi-step method unleashes the full power of the compiler optimizations while using `powi()` with the `for` loop
2. The recursive method computes the polynomial values of the base variable and its derivatives
In the package, [36 thermodynamic, transport and further properties](properties) can be calculated.
The following 12 input pairs are implemented:
txt
(p,t) (p,h) (p,s) (p,v)
(t,h) (t,s) (t,v)
(p,x) (t,x) (h,x) (s,x)
(h,s)
Usage
Install the crate
bash
cargo add seuif97
The type of functions are provided in the package:
txt
struct o_id_region_args {
o_id: i32,
region: i32,
}
fn<R>(f64,f64,R) -> f64
where
R: Into<o_id_region_args>,
* the first,second input parameters(f64) : the input propertry pairs
* the third and fourth input parametes<R>:
* the third : the property ID of the calculated property - [o_id](properties)
* the fourth `option` parameter: the region of IAPWS-IF97
* the return(f64): the calculated property value of o_id
txt
pt<R>(p:f64,t:f64,o_id_region:R)->f64
ph<R>(p:f64,h:f64,o_id_region:R)->f64
ps<R>(p:f64,s:f64,o_id_region:R)->f64
pv<R>(p:f64,v:f64,o_id_region:R)->f64
th<R>(t:f64,h:f64,o_id_region:R)->f64
ts<R>(t:f64,s:f64,o_id_region:R)->f64
tv<R>(t:f64,v:f64,o_id_region:R)->f64
hs<R>(h:f64,s:f64,o_id_region:R)->f64
px(p:f64,x:f64,o_id:i32)->f64
tx(p:f64,x:f64,o_id:i32)->f64
hx(h:f64,x:f64,o_id:i32)->f64
sx(s:f64,x:f64,o_id:i32)->f64
**Example**
rust
use seuif97::*;
fn main() {
let p:f64 = 3.0;
let t:f64= 300.0-273.15;
let h=pt(p,t,OH);
let s=pt(p,t,OS);
// set the region
let v=pt(p,t,(OV,1));
println!("p={p:.6} t={t:.6} h={t:.6} s={s:.6} v={v:.6}");
}
The C binding
**Building the dynamic link library**
* cdecl
bash
cargo build -r --features cdecl
* stdcall: Win32 API functions
bash
cargo build -r --features stdcall
The convenient compiled dynamic link libraries are provided in the [./dynamic_lib/](./dynamic_lib/)
* `seuif97.dll`: [Windows64](./dynamic_lib/windows_x64/) and [Windows32](./dynamic_lib/windows_x86/)
* `libseuif97.so`: [Linux64](./dynamic_lib/linux_x64/)
**The functions in C**
c
double pt(double p,double t,short o_id);
double ph(double p,double h,short o_id);
double ps(double p,double s,short o_id);
double pv(double p,double v,short o_id);
double tv(double t,double v,short o_id);
double th(double t,double h,short o_id);
double ts(double t,double s,short o_id);
double hs(double h,double s,short o_id);
double px(double p,double x,short o_id);
double tx(double t,double x,short o_id);
double hx(double h,double x,short o_id);
double sx(double s,double x,short o_id);
**Examples**
* [./demo_using_lib/](./demo_using_lib/): C, Python, C, Excel VBA, Java, Fortran
c
include <stdlib.h>
include <stdio.h>
include <string.h>
define OH 4
define OS 5
extern double pt(double p,double t,short o_id);
int main(void)
{
double p = 16.0;
double t = 530.0;
double h = pt(p, t, OH);
double s = pt(p, t, OS);
printf("p,t %f,%f h= %f s= %f\n", p, t, h, s);
return EXIT_SUCCESS;
}
The Python binding
[](https://pepy.tech/project/seuif97) [](https://pepy.tech/project/seuif97)
**Install**
bash
pip install seuif97
**Examples**
python
from seuif97 import *
OH=4
p=16.0
t=535.1
??(in1,in2,o_id)
h=pt(p,t,OH)
??2?(in1,in2)
s=pt2s(p,t)
print(f"p={p}, t={t} h={h:.3f} s={s:.3f}")
**T-S Diagram**
* [./demo_using_lib/Diagram_T-S.py](./demo_using_lib/Diagram_T-S.py)
Properties
| Propertry | Unit | Symbol | o_id | o_id(i32)|
| ------------------------------------- | :---------: |:------:|------:|:--------:|
| Pressure | MPa | p | OP | 0 |
| Temperature | °C | t | OT | 1 |
| Density | kg/m³ | ρ | OD | 2 |
| Specific Volume | m³/kg | v | OV | 3 |
| Specific enthalpy | kJ/kg | h | OH | 4 |
| Specific entropy | kJ/(kg·K) | s | OS | 5 |
| Specific exergy | kJ/kg | e | OE | 6 |
| Specific internal energy | kJ/kg | u | OU | 7 |
| Specific isobaric heat capacity | kJ/(kg·K) | cp | OCP | 8 |
| Specific isochoric heat capacity | kJ/(kg·K) | cv | OCV | 9 |
| Speed of sound | m/s | w | OW | 10 |
| Isentropic exponent | | k | OKS | 11 |
| Specific Helmholtz free energy | kJ/kg | f | OF | 12 |
| Specific Gibbs free energy | kJ/kg | g | OG | 13 |
| Compressibility factor | | z | OZ | 14 |
| Steam quality | | x | OX | 15 |
| Region | | r | OR | 16 |
| Isobari cubic expansion coefficient | 1/K | ɑv | OEC | 17 |
| Isothermal compressibility | 1/MPa | kT | OKT | 18 |
| Partial derivative (∂V/∂T)p | m³/(kg·K) |(∂V/∂T)p| ODVDT | 19 |
| Partial derivative (∂V/∂p)T | m³/(kg·MPa) |(∂v/∂p)t| ODVDP | 20 |
| Partial derivative (∂P/∂T)v | MPa/K |(∂p/∂t)v| ODPDT | 21 |
| Isothermal throttling coefficient | kJ/(kg·MPa) | δt | OIJTC | 22 |
| Joule-Thomson coefficient | K/MPa | μ | OJTC | 23 |
| Dynamic viscosity | Pa·s | η | ODV | 24 |
| Kinematic viscosity | m²/s | ν | OKV | 25 |
| Thermal conductivity | W/(m.K) | λ | OTC | 26 |
| Thermal diffusivity | m²/s | a | OTD | 27 |
| Prandtl number | | Pr | OPR | 28 |
| Surface tension | N/m | σ | OST | 29 |
| Static Dielectric Constant | | ε | OSDC | 30 |
| Isochoric pressure coefficient | 1/K | β | OPC | 31 |
| Isothermal stress coefficient | kg/m³ | βp | OBETAP| 32 |
| Fugacity coefficient | | fi | OFI | 33 |
| Fugacity | MPa | f* | OFU | 34 |
| Relative pressure coefficient | 1/K | αp | OAFLAP| 35|