Function reynolds_number 

pub fn reynolds_number(
    density: f64,
    velocity: f64,
    characteristic_length: f64,
    dynamic_viscosity: f64,
) -> Option<f64>

Computes Reynolds number from density, velocity, characteristic length, and dynamic viscosity.

Formula: Re = ρ * v * L / μ

Returns None when density is negative, when characteristic_length is negative, when dynamic_viscosity is less than or equal to zero, when any input is not finite, or when the computed result is not finite.

Examples

use use_fluid::reynolds_number;

let reynolds = reynolds_number(1000.0, 2.0, 0.1, 0.001).unwrap();

assert!((reynolds - 200_000.0).abs() < 1.0e-9);