pravash 0.24.3

Fluid dynamics simulation — SPH, Euler/Navier-Stokes, shallow water, buoyancy, drag, vortex dynamics
Documentation

Pravash

Pravash (Sanskrit: प्रवास — journey, flow) — fluid dynamics simulation for AGNOS

CI License: GPL-3.0 crates.io docs.rs

Particle-based and grid-based fluid simulation. SPH for real-time effects, Euler/Navier-Stokes for accurate simulation, shallow water for surface waves, multi-phase for immiscible fluids, viscoelastic for honey/lava, heat transfer and combustion for fire effects. Built on hisab for math foundations.

Non-linear SWE, Manning friction, wetting/drying, wave breaking, Boussinesq dispersion, terrain-following, multi-phase SPH, phase-field interface tracking, Oldroyd-B viscoelasticity, heat conduction, combustion, Rayon parallelism, GPU-agnostic compute interface — zero unsafe, 230+ tests.

Installation

[dependencies]
pravash = "0.24"

Default features: sph, grid, shallow.

Optional: buoyancy, vortex, coupling, compute, parallel, ai, logging.

MSRV: 1.89 (Rust edition 2024).

Features

Feature Default Description
sph yes Smoothed Particle Hydrodynamics — particle-based fluids
grid yes Euler/Navier-Stokes grid-based solver
shallow yes Non-linear shallow water equations — 2D surface waves
buoyancy no Buoyancy, drag, Reynolds number, flow regime
vortex no Vorticity, Lamb-Oseen/Rankine vortices, enstrophy, Kolmogorov scale
coupling no Fluid-body interaction, FLIP/PIC hybrid, level set, added mass
compute no GPU-agnostic ComputeBackend trait, packed f32 buffers
parallel no Rayon parallelism for SPH and grid operations
ai no Daimon/hoosh integration (network deps)
logging no Structured logging + chrome://tracing profiling via PRAVASH_LOG
full -- Enables all features

Quick Start

use pravash::sph::{SphSolver, create_particle_block, total_kinetic_energy};
use pravash::common::{FluidConfig, FluidMaterial};

let mut particles = create_particle_block([0.2, 0.5], [0.3, 0.3], 0.02, 0.001);
let config = FluidConfig::water_2d();
let mut solver = SphSolver::new();

for _ in 0..100 {
    solver.step(&mut particles, &config, FluidMaterial::WATER.viscosity).unwrap();
}

println!("KE: {}", total_kinetic_energy(&particles));

Modules

Module Description
sph SPH solver with spatial hash acceleration, PCISPH, surface tension, adaptive timestep, multi-phase (per-phase EOS/viscosity/interface tension), viscoelastic (Oldroyd-B), heat conduction, combustion
grid Navier-Stokes: semi-Lagrangian + MacCormack advection, diffusion, DST + GS pressure projection, vorticity confinement, buoyancy, periodic boundaries. Rayon-parallelized advection and projection
shallow Non-linear SWE with convective terms, flux-form continuity, Manning bed friction, wetting/drying, wave breaking detection + dissipation, Boussinesq dispersion, well-balanced terrain-following
phase_field Allen-Cahn phase-field interface tracking with advection and double-well relaxation
buoyancy Archimedes buoyancy, drag force, terminal velocity, Reynolds number, flow regime classification
vortex Vorticity, Lamb-Oseen/Rankine vortex models, enstrophy, Kolmogorov microscale
coupling RigidBody interaction (sphere/box SDF), FLIP/PIC hybrid, particle-level set, added mass, field drag
compute GPU-agnostic ComputeBackend trait, PackedParticles f32 buffer packing, kernel parameter structs
common FluidParticle (with phase, temperature, fuel, conformation tensor), FluidMaterial (water/oil/honey/air/lava), FluidConfig, ParticleSoa (SOA layout), ParticleArena (memory pool)

Examples

Example Features Description
basic_fluid sph SPH dam break with SphSolver, kinetic energy tracking
shallow_water shallow Shallow water splash with Manning friction
multiphase sph Water-oil two-phase simulation with interface tension

Run an example:

cargo run --example basic_fluid --features sph
cargo run --example shallow_water --features shallow
cargo run --example multiphase --features sph

Architecture

pravash (this crate)
  +-- hisab (math: vectors, spatial hash, FFT/DST, PDE solvers)

Consumer Crates

Crate Usage
kiran Water, smoke, fire effects
joshua Fluid simulation
impetus Fluid-body interaction

Documentation

Building

cargo build --all-features
cargo test --all-features

License

GPL-3.0 — see LICENSE.