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 for the given spatial grid, initialized to zero state.

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

Populate the macroscopic state from per-cell kinetic moments (flat arrays of length N).

pub fn step(&mut self, dt: f64, gx: &[f64], gy: &[f64], gz: &[f64])

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

gx, gy, gz provide the gravitational acceleration components at each cell as separate flat arrays of length nxnynz.

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

Extract the density field as a flat array from the macroscopic state.

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

Extract the three momentum-density components [Jx, Jy, Jz] as flat arrays.

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

Extract the energy-density field as a flat array from the macroscopic state.

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).