{
  "problem": "Continuous-source tracer in a uniform 1D flow (Ogata & Banks 1961): c = c0 at x = 0 from t = 0, initially clean.",
  "domain": {
    "xmin": 0.0,
    "xmax": 1000.0
  },
  "flow": {
    "u_ms": 0.1,
    "D_m2s": 0.01
  },
  "source": {
    "c0": 1.0
  },
  "boundaries": {
    "x0": "Dirichlet c = c0",
    "xmax": "zero gradient"
  }
}