KiThe 0.1.4

A collection of structures and functions useful for chemical kinetics, chemical thermodynamics, combustion, heat and mass transfer, shock tubes and so on and so far. Work in progress. Advices and contributions will be appreciated
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//v 0.1.1
#![allow(warnings)]
use RustedSciThe::symbolic::symbolic_engine::Expr;
use serde::{Deserialize, Serialize};
use std::collections::{HashMap, HashSet};
use std::f64;

const R: f64 = 8.314;
const Rsym: Expr = Expr::Const(8.314);
// Different types of reactions proceeding here

// Struct for reaction type "elementary" with simplest form of
// kinetic constant - easy Arrhenius form  A*Temp.powf(*n)exp(-E/(Temp*R) )
#[derive(Debug, Deserialize, Serialize, Clone)]
pub struct ElementaryStruct {
    pub Arrenius: Vec<f64>,
}

impl ElementaryStruct {
    pub fn new(Arrenius: Vec<f64>) -> Self {
        Self { Arrenius }
    }
    pub fn K_const(&self, Temp: f64) -> f64 {
        let A: &f64 = &self.Arrenius[0];
        let n: &f64 = &self.Arrenius[1];
        let E: &f64 = &self.Arrenius[2];
        let K_const_: f64 = A * Temp.powf(*n) * f64::exp(-E / (Temp * R));
        return K_const_;
    }
    pub fn K_expr(&self, T: Expr) -> Expr {
        let A: f64 = self.Arrenius[0];
        let n: f64 = self.Arrenius[1];
        let E: f64 = self.Arrenius[2];
        let A = Expr::Const(A);
        let n = Expr::Const(n);
        let E = Expr::Const(E);
        let k0 = A * (T.clone()).pow(n);
        let k = k0 * (E / (Rsym * T)).exp();
        return k;
    }
}

// Struct for reaction type "falloff" - form of kinetic constant is more compicated
#[derive(Debug, Deserialize, Serialize, Clone)]
pub struct FalloffStruct {
    pub low_rate: Vec<f64>,
    pub high_rate: Vec<f64>,
    pub eff: HashMap<String, f64>,
    pub troe: Option<Vec<f64>>,
}
impl FalloffStruct {
    pub fn new(
        low_rate: Vec<f64>,
        high_rate: Vec<f64>,
        eff: HashMap<String, f64>,
        troe: Option<Vec<f64>>,
    ) -> Self {
        Self {
            low_rate,
            high_rate,
            eff,
            troe: None,
        }
    }
    pub fn K_const(&self, Temp: f64, Concentrations: HashMap<String, f64>) -> f64 {
        //
        let k_l = &self.low_rate[0];
        let b_l = &self.low_rate[1];
        let E_l = &self.low_rate[2];
        //
        let k_h = &self.high_rate[0];
        let b_h = &self.high_rate[1];
        let E_h = &self.high_rate[2];

        let K0 = k_l * f64::exp(-E_l / (R * Temp)) * Temp.powf(*b_l);
        let K_inf = k_h * f64::exp(-E_h / (R * Temp)) * Temp.powf(*b_h);
        let P_r = K0 / K_inf;
        // Calculate effective concentrations, e.g., by multiplying concentrations with coefficients from self.eff
        // Hashmap {substance: concentration}
        let mut Eff: f64 = 0.0;
        for (subs_name, C_i) in Concentrations.iter() {
            if self.eff.get(subs_name).is_some() {
                self.eff.get(subs_name).map(|&eff_i| Eff += eff_i * C_i);
            } else {
                Eff += C_i;
            };
            return Eff;
        }
        let k: f64 = {
            if let Some(troe) = &self.troe {
                let F_c = if troe.len() == 3 {
                    let A: f64 = troe[0];
                    let T_3 = troe[1];
                    let T_1 = troe[2];
                    let F_c = (1.0 - A) * f64::exp(-Temp / T_3) + A * f64::exp(-Temp / T_1);
                    F_c
                }
                //troe.len()==3
                else if troe.len() == 4 {
                    let A: f64 = troe[0];
                    let T_3 = troe[1];
                    let T_1 = troe[2];
                    let T_2 = troe[3];
                    let F_c = (1.0 - A) * f64::exp(-Temp / T_3)
                        + A * (f64::exp(-Temp / T_1) + f64::exp(-Temp / T_2));
                    F_c
                }
                //troe.len()==4
                else {
                    println!("Error in Troe parameters");
                    return 0.0;
                }; //troe.len()!=3,4
                let C: f64 = -0.4 - 0.67 * f64::log(F_c, 10.0);
                let N: f64 = 0.75 - 1.27 * f64::log(F_c, 10.0);
                let f_1: f64 = (f64::log(P_r, 10.0) + C) / (N - 0.14 * (f64::log(P_r, 10.0) + C));
                let F = 10.0_f64.powf(f64::log(F_c, 10.0) / (1.0 + f_1.powf(2.0)));
                let k = K_inf * (P_r / (1.0 + P_r)) * F;
                return k;
            } else {
                // there is no troe field
                let k = K_inf * (P_r / (1.0 + P_r));
                return k;
            }; //troe
        }; //k

        let K_const_: f64 = Eff * k;
        return K_const_;
    }
}

#[derive(Debug, Deserialize, Serialize, Clone)]
pub struct PressureStruct {
    pub Arrenius: HashMap<i32, Vec<f64>>,
}

impl PressureStruct {
    pub fn new(r#type: String, Arrenius: HashMap<i32, Vec<f64>>, eq: String) -> Self {
        Self { Arrenius }
    }
    pub fn K_const(&self, Temp: &f64, P: f64) -> f64 {
        let pressures: Vec<f64> = self.Arrenius.keys().map(|p| *p as f64).collect::<Vec<_>>();

        let location =
            pressures.binary_search_by(|v| v.partial_cmp(&Temp).expect("Couldn't compare values"));
        let k: f64 = {
            match location {
                //
                Ok(i) => println!("Found at {}", i),
                Err(i) => println!("Not found, could be inserted at {}", i),
            }
            return 0.0;
        };
    }
}

#[derive(Debug, Deserialize, Serialize, Clone)]
pub struct ThreeBodyStruct {
    pub Arrenius: Vec<f64>,
    pub eff: HashMap<String, f64>,
}

//
impl ThreeBodyStruct {
    pub fn new(Arrenius: Vec<f64>, eff: HashMap<String, f64>) -> Self {
        Self { Arrenius, eff }
    }
    pub fn K_const(&self, Temp: f64, Concentrations: HashMap<String, f64>) -> f64 {
        let A: &f64 = &self.Arrenius[0];
        let n: &f64 = &self.Arrenius[1];
        let E: &f64 = &self.Arrenius[2];
        // Hashmap {substance: concentration}
        let mut Eff: f64 = 0.0;
        for (subs_name, C_i) in Concentrations.iter() {
            if self.eff.get(subs_name).is_some() {
                self.eff.get(subs_name).map(|&eff_i| Eff += eff_i * C_i);
            } else {
                Eff += C_i;
            };
            return Eff;
        }
        let K_const_: f64 = Eff * A * Temp.powf(*n) * f64::exp(-E / (Temp * R));
        return K_const_;
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_elementary_reaction() {
        let elementary_reaction = ElementaryStruct::new(vec![1.0, 2.0, 300.0]);

        let temp = 298.0; // 298K
        let expected_k_const = 1.0 * (298.0_f64).powf(2.0) * f64::exp(-300.0 / (298.0 * 8.314));
        assert!((elementary_reaction.K_const(temp) - expected_k_const).abs() < 1e-6);
    }

    #[test]
    fn test_falloff_reaction() {
        let falloff_reaction = FalloffStruct::new(
            vec![1.0, 2.0, 300.0],
            vec![10.0, 1.5, 400.0],
            HashMap::from([("H2".to_string(), 2.0), ("M".to_string(), 1.0)]),
            Some(vec![0.5, 300.0, 1000.0]),
        );

        let temp = 298.0; // 298K
        let concentrations = HashMap::from([("H2".to_string(), 2.0), ("M".to_string(), 1.0)]);
        let expected_k_const = falloff_reaction.K_const(temp, concentrations);
        assert!(expected_k_const > 0.0);
    }
    /*
    #[test]
    fn test_pressure_reaction() {
        let pressure_reaction = PressureStruct::new(
            "pressure".to_string(),
            HashMap::from([(1.0, vec![1.0, 2.0, 300.0])]),
            "H2+M<=>H+H+M".to_string(),
        );

        let temp = 298.0; // 298K
        let pressure = 1.0; // 1 atm
        // The K_const method for pressure reactions is not implemented in the provided code.
        // You would need to implement it based on the specific requirements of pressure-dependent reactions.
        // For now, we'll just assert that the method does not panic.
        assert!(!pressure_reaction.K_const(&temp, pressure).is_nan());
    }
    */
    #[test]
    fn test_threebody_reaction() {
        let threebody_reaction = ThreeBodyStruct::new(
            vec![1.0, 2.0, 300.0],
            HashMap::from([("H2".to_string(), 2.0), ("M".to_string(), 1.0)]),
        );

        let temp = 298.0; // 298K
        let concentrations = HashMap::from([("H2".to_string(), 2.0), ("M".to_string(), 1.0)]);
        let expected_k_const = threebody_reaction.K_const(temp, concentrations);
        assert!(expected_k_const > 0.0);
    }
}