User-Facing API

The recommended programmatic interface is the small API exposed from scp. It lets applications construct fluids and evaluate properties without importing the concrete fluid classes directly.

Examples:

from scp import get_fluid

water = get_fluid("water")
water_density = water.density(25.0)

pg = get_fluid("propylene_glycol", concentration=0.4)
pg_viscosity = pg.viscosity(20.0)

User-defined fluids can be created through the same API. The core properties can be constants or callables that accept temperature in Celsius:

from scp import get_fluid

fluid = get_fluid(
    "user_defined",
    name="CustomFluid",
    viscosity=lambda temp: 0.003 - 1.0e-5 * temp,
    specific_heat=3200.0,
    density=lambda temp: 1000.0 - 0.5 * temp,
    conductivity=0.42,
    freeze_point=-12.0,
    t_min=-20.0,
    t_max=80.0,
)

print(fluid.density(20.0))

scp.api.available_fluids(*, include_user_defined: bool = True) → tuple[str, ...]

Return the fluid keys accepted by get_fluid().

@param include_user_defined: Include the key for user-defined fluids @return: Supported fluid keys

scp.api.available_properties() → tuple[str, ...]

Return the property keys supported by fluid instances and the CLI.

@return: Supported property keys

scp.api.get_fluid(fluid: str, *, concentration: float = 0.0, properties: UserDefinedProperties | Mapping[str, object] | None = None, **user_defined_options: object) → BaseFluid

Construct a fluid from the user-facing API.

@param fluid: Fluid key @param concentration: Mixture concentration fraction for built-in mixture fluids @param properties: User-defined property values @param user_defined_options: User-defined fluid options and property values @return: Fluid instance