"""Spec-backed runtime classes for modified NACA 4-digit airfoils."""
from __future__ import annotations
from copy import deepcopy
from typing import Literal, Self
from .airfoil import OrthogonalAirfoil
from .airfoil_schema import (
Naca4ModifiedAirfoilParamsSpec,
Naca4ModifiedAirfoilSpec,
)
from .naca4_airfoil import (
NACA4_MAX_CAMBER_LIMIT,
NACA4_MAX_CAMBER_LOCATION_LIMIT,
NACA4_MAX_THICKNESS_LIMIT,
)
from .naca4_camber import Naca4DigitCamber
from .naca45_modified_thickness import (
LEADING_EDGE_INDEX_MAX,
LEADING_EDGE_INDEX_MIN,
MAX_THICKNESS_LOCATION_MAX,
MAX_THICKNESS_LOCATION_MIN,
Naca45DigitModifiedThicknessClassic,
Naca45DigitModifiedThicknessParams,
)
NACA4_MODIFIED_DESIGNATION_LENGTH = 7
NACA4_MODIFIED_DESIGNATION_DASH_INDEX = 4
NACA4_MODIFIED_MIN_THICKNESS_LOCATION = 0.1
def _validate_naca4_modified_designation(designation: str) -> None:
"""
Validate a modified NACA 4-digit designation string.
Parameters
----------
designation : str
Modified NACA 4-digit designation string in ``####-##`` form.
Raises
------
ValueError
If ``designation`` does not match the supported modified-series
format.
"""
if len(designation) != NACA4_MODIFIED_DESIGNATION_LENGTH:
raise ValueError(
"Modified NACA 4-digit designations must be 7 characters."
)
if designation[NACA4_MODIFIED_DESIGNATION_DASH_INDEX] != "-":
raise ValueError(
"Modified NACA 4-digit designations must use the form ####-##."
)
digits = designation.replace("-", "")
if not digits.isdigit():
raise ValueError(
"Modified NACA 4-digit designations must contain only digits."
)
def _validate_naca4_modified_params(
params: Naca4ModifiedAirfoilParamsSpec,
) -> None:
"""
Validate the explicit modified NACA 4-digit parameters.
Parameters
----------
params : Naca4ModifiedAirfoilParamsSpec
Explicit modified NACA 4-digit parameter specification to validate.
Raises
------
ValueError
If any parameter violates the supported modified-series bounds or
consistency rules.
"""
if not 0.0 <= params.m < NACA4_MAX_CAMBER_LIMIT:
raise ValueError(
"Modified NACA 4-digit parameter m must satisfy 0 <= m < 0.1."
)
if not 0.0 <= params.p <= NACA4_MAX_CAMBER_LOCATION_LIMIT:
raise ValueError(
"Modified NACA 4-digit parameter p must satisfy 0 <= p <= 0.9."
)
if not 0.0 <= params.t <= NACA4_MAX_THICKNESS_LIMIT:
raise ValueError(
"Modified NACA 4-digit parameter t must satisfy 0 <= t <= 0.4."
)
if params.m == 0.0 and params.p != 0.0:
raise ValueError(
"Modified NACA 4-digit parameter p must be 0 when m is 0."
)
if params.m > 0.0 and params.p <= 0.0:
raise ValueError(
"Modified NACA 4-digit parameter p must be positive when m > 0."
)
if (
not LEADING_EDGE_INDEX_MIN
<= params.leading_edge_index
< (LEADING_EDGE_INDEX_MAX)
):
raise ValueError(
"Modified NACA 4-digit leading_edge_index must satisfy "
"1 <= leading_edge_index < 10."
)
if not (
NACA4_MODIFIED_MIN_THICKNESS_LOCATION
<= params.max_thickness_location
< 1.0
):
raise ValueError(
"Modified NACA 4-digit max_thickness_location must satisfy "
"0.1 <= max_thickness_location < 1.0."
)
def _copy_naca4_modified_spec(
spec: Naca4ModifiedAirfoilSpec,
) -> Naca4ModifiedAirfoilSpec:
"""
Return a defensive copy of a modified NACA 4-digit spec.
Parameters
----------
spec : Naca4ModifiedAirfoilSpec
Source specification to copy.
Returns
-------
Naca4ModifiedAirfoilSpec
Deep copy of ``spec``.
"""
return deepcopy(spec)
def _designation_to_lmti(designation: str) -> float:
"""
Return the max-thickness-location index from a designation.
Parameters
----------
designation : str
Modified NACA 4-digit designation string.
Returns
-------
float
Max-thickness-location index extracted from ``designation``.
Raises
------
ValueError
If the designation encodes an unsupported thickness-location index.
"""
lmti = float(designation[6])
if not MAX_THICKNESS_LOCATION_MIN <= lmti < MAX_THICKNESS_LOCATION_MAX:
raise ValueError(
"Modified NACA 4-digit max thickness location must be 1-9."
)
return lmti
[docs]
class Naca4ModifiedAirfoilClassic(OrthogonalAirfoil):
"""
Classic modified NACA 4-digit airfoil built from a designation.
Parameters
----------
spec : Naca4ModifiedAirfoilSpec
Serialized specification containing a modified-series designation.
Raises
------
ValueError
If ``spec`` does not contain a valid designation-only definition.
"""
[docs]
def __init__(self, spec: Naca4ModifiedAirfoilSpec) -> None:
"""
Build a classic modified NACA 4-digit airfoil from its spec.
Parameters
----------
spec : Naca4ModifiedAirfoilSpec
Serialized specification containing a modified-series
designation.
Raises
------
ValueError
If ``spec`` does not contain a valid designation-only
definition.
"""
if spec.designation is None or spec.params is not None:
raise ValueError(
"Classic modified NACA 4-digit airfoils require "
"designation-only specs."
)
_validate_naca4_modified_designation(spec.designation)
lmti = _designation_to_lmti(spec.designation)
camber = Naca4DigitCamber(
mci=float(spec.designation[0]),
lci=float(spec.designation[1]),
)
thickness = Naca45DigitModifiedThicknessClassic(
mti=float(spec.designation[2:4]),
lei=float(spec.designation[5]),
lmti=lmti,
)
super().__init__(camber=camber, thickness=thickness)
self._spec = _copy_naca4_modified_spec(spec)
[docs]
@classmethod
def from_designation(cls, designation: str) -> Self:
"""
Build a classic modified NACA 4-digit airfoil from a designation.
Parameters
----------
designation : str
Modified NACA 4-digit designation such as ``"0003-64"``.
Returns
-------
Self
Runtime airfoil built from ``designation``.
Raises
------
ValueError
If ``designation`` is not a valid modified NACA 4-digit code.
"""
return cls(Naca4ModifiedAirfoilSpec(designation=designation))
@property
def spec(self) -> Naca4ModifiedAirfoilSpec:
"""
Return the source spec for this airfoil.
Returns
-------
Naca4ModifiedAirfoilSpec
Defensive copy of the serialized source spec.
"""
return _copy_naca4_modified_spec(self._spec)
[docs]
def to_spec(self) -> Naca4ModifiedAirfoilSpec:
"""
Return the schema definition needed to recreate this airfoil.
Returns
-------
Naca4ModifiedAirfoilSpec
Serialized source spec for this airfoil.
"""
return self.spec
[docs]
class Naca4ModifiedAirfoilParams(OrthogonalAirfoil):
"""
Parametric modified NACA 4-digit airfoil built from explicit params.
Parameters
----------
spec : Naca4ModifiedAirfoilSpec
Serialized specification containing explicit modified-series
parameters.
Raises
------
ValueError
If ``spec`` does not contain a valid params-only definition.
"""
[docs]
def __init__(self, spec: Naca4ModifiedAirfoilSpec) -> None:
"""
Build a parametric modified NACA 4-digit airfoil from its spec.
Parameters
----------
spec : Naca4ModifiedAirfoilSpec
Serialized specification containing explicit modified-series
parameters.
Raises
------
ValueError
If ``spec`` does not contain a valid params-only definition.
"""
if spec.designation is not None or spec.params is None:
raise ValueError(
"Parametric modified NACA 4-digit airfoils require "
"params-only specs."
)
_validate_naca4_modified_params(spec.params)
camber = Naca4DigitCamber(
mci=100.0 * spec.params.m,
lci=10.0 * spec.params.p,
)
thickness = Naca45DigitModifiedThicknessParams(
mti=100.0 * spec.params.t,
lei=spec.params.leading_edge_index,
lmti=10.0 * spec.params.max_thickness_location,
closed_te=spec.params.trailing_edge == "sharp",
)
super().__init__(camber=camber, thickness=thickness)
self._spec = _copy_naca4_modified_spec(spec)
[docs]
@classmethod
def from_params(
cls,
*,
m: float,
p: float,
t: float,
leading_edge_index: float,
max_thickness_location: float,
trailing_edge: Literal["standard", "sharp"] = "standard",
) -> Self:
"""
Build a parametric modified NACA 4-digit airfoil from params.
Parameters
----------
m : float
Maximum camber as a fraction of chord.
p : float
Chordwise location of maximum camber as a fraction of chord.
t : float
Maximum thickness as a fraction of chord.
leading_edge_index : float
Modified-series leading-edge shape index.
max_thickness_location : float
Chordwise location of maximum thickness as a fraction of chord.
trailing_edge : {"standard", "sharp"}, default="standard"
Trailing-edge closure model for the thickness distribution.
Returns
-------
Self
Runtime airfoil built from the explicit parameters.
Raises
------
ValueError
If the parameter set falls outside the supported modified-series
range.
"""
params = Naca4ModifiedAirfoilParamsSpec(
m=m,
p=p,
t=t,
leading_edge_index=leading_edge_index,
max_thickness_location=max_thickness_location,
trailing_edge=trailing_edge,
)
return cls(Naca4ModifiedAirfoilSpec(params=params))
@property
def spec(self) -> Naca4ModifiedAirfoilSpec:
"""
Return the source spec for this airfoil.
Returns
-------
Naca4ModifiedAirfoilSpec
Defensive copy of the serialized source spec.
"""
return _copy_naca4_modified_spec(self._spec)
[docs]
def to_spec(self) -> Naca4ModifiedAirfoilSpec:
"""
Return the schema definition needed to recreate this airfoil.
Returns
-------
Naca4ModifiedAirfoilSpec
Serialized source spec for this airfoil.
"""
return self.spec
__all__ = [
"Naca4ModifiedAirfoilClassic",
"Naca4ModifiedAirfoilParams",
]