{
  "problem": "Frictionless pipe, reservoir at x = 0, valve at x = L closed instantaneously at t = 0.",
  "pipe": {
    "L_m": 1000.0,
    "wave_speed_ms": 1000.0
  },
  "initial_condition": {
    "V0_ms": 1.0,
    "p0_pa": 0.0
  },
  "fluid": {
    "rho_kgm3": 1000.0
  },
  "boundaries": {
    "x0": "constant-head reservoir",
    "xL": "closed valve (t > 0)"
  }
}