{
    "grids": {
        "default": {
            "operators": {
                "xi": "upwind9",
                "eta": "upwind9"
            },
            "boundary_conditions": {
                "south": "vortex",
                "north": "vortex",
                "east": "vortex",
                "west": "vortex"
            }
        },
        "grid0": {
            "x": { "linspace": { "start": -5, "end": 5, "steps": 50 } },
            "y": { "linspace": { "start": 0, "end": 5, "steps": 25 } },
            "boundary_conditions": {
                "south": {"interpolate": { "neighbour": "grid1", "operator": "9"}}
            }
        },
        "grid1": {
            "x": { "linspace": { "start": -5, "end": 5, "steps": 99 } },
            "y": { "linspace": { "start": -5, "end": 0, "steps": 50 } },
            "boundary_conditions": {
                "north": {"interpolate": { "neighbour": "grid0", "operator": "9"}}
            }
        }
    },
    "integration_time": 2.0,
    "vortex": {
        "vortices": [{
            "x0": -1.0,
            "y0": 0.0,
            "rstar": 0.5,
            "eps": 1.0
        }],
        "mach": 0.5
    }
}