"""Compile-time gas property constants. No Python property evaluator."""
from __future__ import annotations
from dataclasses import dataclass

@dataclass(frozen=True)
class IdealGasMedium:
    name: str = 'SimpleAirApprox'
    R_gas: float = 287.0
    cp_ref: float = 1005.0
    T_ref: float = 300.0
    cp_slope: float = 0.0
    viscosity_ref: float = 1.82e-05
    viscosity_T_ref: float = 293.15
    sutherland_constant: float = 110.4

GasMedium = IdealGasMedium