Entropyk/apps/web

Entropyk Web UI

Visual canvas builder for Entropyk thermodynamic cycles.

The UI emits the same ScenarioConfig JSON as the CLI (crates/cli/src/config.rs). Physics always runs through entropyk_cli::run::simulate_from_json via the Axum ui-server.

Prerequisites

• Node.js 18+ and npm
• The Rust API server running (see below)

Setup

1. Start the Rust API server

From the project root:

cargo run -p entropyk-demo --bin ui-server
# → http://localhost:3030

Endpoints:

• GET /api/health
• GET /api/components
• POST /api/simulate
• GET /api/mollier?fluid=R134a

2. Start the Next.js dev server

cd apps/web
npm install
npm run dev
# → http://localhost:3000

By default the frontend proxies /api/entropyk/* to http://localhost:3030/api/* (see next.config.mjs). To point at a different API, set:

ENTROPYK_API_URL=http://my-host:3030 npm run dev

Usage

1. Drag components from the left palette onto the canvas.
2. Connect ports by dragging from one handle to another.
3. Select a node to edit its parameters in the right panel.
4. Pick the fluid and backend in the top bar.
5. Click Solve cycle — the result panel shows COP, edge states and a P-h diagram.
6. Load drops in a CLI example from the picker; Import JSON loads any CLI config.
7. Multi-run sweeps parameters (fluid, UA, …) and solves cases in parallel.

Architecture

Browser (Next.js)         Rust API (Axum ui-server :3030)
  React Flow canvas   →   POST /api/simulate
  Zustand store             → simulate_from_json() (CLI engine)
  Recharts P-h diagram  ←   SimulationResult JSON

Anything buildable in the UI can also be run with:

cargo run -p entropyk-cli -- run path/to/config.json

Deprecated surfaces

• ui/ at the repo root — legacy static HTML; calls removed /api/calculate. Do not use.
• tools/circuit-builder-ui — alternate HTML builder; prefer apps/web.