Struct KfvsSolver 

pub struct KfvsSolver {
    pub shape: [usize; 3],
    pub dx: [f64; 3],
    pub state: Vec<MacroState>,
}

KFVS macroscopic solver on a 3D spatial grid.

Evolves (ρ, ρu, e) using kinetic flux vector splitting. The KFVS flux at cell interface i+½ in direction d is:

F⁺ = ∫{v_d > 0} v_d * [1, v, ½|v|²]ᵀ * f⁺ dv F⁻ = ∫{v_d < 0} v_d * [1, v, ½|v|²]ᵀ * f⁻ dv

where f⁺/f⁻ are Maxwellians reconstructed from left/right cell states.

Fields

shape: [usize; 3]

Spatial grid shape [nx, ny, nz].

dx: [f64; 3]

Cell spacings [dx, dy, dz].

state: Vec<MacroState>

Macroscopic state: one MacroState per spatial cell (row-major).

Implementations

impl KfvsSolver

pub fn new(shape: [usize; 3], dx: [f64; 3]) -> Self

Create a KFVS solver from initial macroscopic moments.

pub fn initialize_from_moments( &mut self, density: &[f64], momentum_x: &[f64], momentum_y: &[f64], momentum_z: &[f64], energy: &[f64], )

Initialize from kinetic moments computed from the distribution function.

pub fn step(&mut self, dt: f64, acceleration: &[[f64; 3]])

Advance the macroscopic state by one time step Δt using KFVS.

acceleration provides the gravitational field a(x) at each cell, stored as three flat arrays [ax, ay, az] each of length nxnynz.

pub fn density_field(&self) -> Vec<f64>

Extract density field from macroscopic state.

pub fn momentum_field(&self) -> [Vec<f64>; 3]

Extract momentum field components.

pub fn energy_field(&self) -> Vec<f64>

Extract energy field.

pub fn total_mass(&self) -> f64

Total mass (sum of ρ * dx³).

pub fn total_momentum(&self) -> [f64; 3]

Total momentum (sum of J * dx³).

pub fn total_energy(&self) -> f64

Total energy (sum of e * dx³).