Define JSON Schema

[michaelweinold]

...the data schema for the carculator (compare the carculator/data/default_parameters.json) is:

unique_id
  name
  year
  powertrain
  sizes
  (data)
  (metadata)

This is already reasonably abstract. For aircraft, we could simply change some of the field names:

🚗	🛩️
powertrain	propulsion
sizes	pax or MTOW or ???
no correspondence	design-concept

The way I understand, the powertrain field already allows to "combine" powertrains (eg. hybrid-electric), by listing them as separate categories.

In aircraft, Hydrogen could be used by:

1. directly burning it in the turbine
2. convert it to electricity in a fuel cell

We could use the carculator powertrain logic to describe these cases as:

"propulsion" = "hydrogen-fuelcell"
"propulsion" = "hydrogen-gasturbine"
"propulsion" = "liquidfuel"
"propulsion" = "liquidfuel-hybrid-batteryelectric"

It might make sense to merge the design-concept into this descriptor also:

"propulsion-design" = "liquidfuel-hybrid-batteryelectric-blendedwingbody"

@romainsacchi, is this a good way to describe aircraft typologies?

[romainsacchi]

3rd use case: hydrogen could also be used via a fuel cell (e.g., for cruising) AND combusted (e.g., for take-off), some sort of hybrid gig.

Regarding sizes, I was thinking more of "narrow body", "blended wing body", etc. (so, what you refer to as design), and have the seating capacity has an input parameter specific to each size. But, to be discussed.

For the propulsion terms, I'd suggest using acronyms as we do in carculator: TJ-k ? (turbojet vehicle using kerosene), TJV-h, FCV-h? I don't know, something like that.

[julienmctighe]

I have been categorizing existing studies using the following. Additions to the discussion are italicized.

• Airframe Configuration: Tube and Wing, Blended Wing Body, Retrofit
• Propulsion Type: Hydrogen Combustion, Hydrogen Fuel Cell, Hydrogen Hybrid (H2 Combustion / H2 Fuel Cell), Multi-Fuel Combustion (H2 Combustion / Kerosene Combustion)
• Propulsion Configuration: Conventional, Distributed, Boundary Layer Ingestion
• Size: Commuter, Regional, Small Narrow Body, Large Narrow Body, Small Wide Body, Large Wide Body

[michaelweinold]

Following discussions with @julienmctighe and @romainsacchi on 23.01.2024, we are suggesting a schema of the kind:

"uniqueid": {
    "parameter": "seats",
    "year": 2000,
    "fuselage": "TW",
    "energy_source": "H2",
    "energy_conversion": "FC",
    "transmission": "Elec",
    "propulsion": "Prop",
    "drag_reduction": "None",
    "sizes": [
        "commuter",
        "regional",
        "SNB",
        "LNB",
        "SWB",
        "LWB"
    ],
    "amount": 75,
    "loc": 75,
    "minimum": 50,
    "maximum": 100,
    "kind": "distribution",
    "uncertainty_type": 5,
    "source": "Cox et al. (2018)",
    "url":  "https://doi.org/10.1016/j.trd.2017.10.017"
    "comment": "for testing purposes only"
},

This can be finalized over the coming weeks. For now, we're working with this schema.