engine.pipeline.thermal.ablative_cooling Namespace Reference

Functions
float	ablation_energy_per_mass (AblativeCoolingConfig cfg, float surface_temperature)
float	blowing_reduction (AblativeCoolingConfig cfg, float pyrolysis_mdot, Optional[float] gas_mdot)
Dict[str, object]	liner_response (gas, contour, AblativeCoolingConfig cfg, float x_liner_end, float gas_mdot, Optional[float] surface_temperature=None, bool with_profile=False)

Detailed Description

Ablative liner: quasi-steady surface ablation along the real contour.

The char surface sits at the material's ablation temperature while it recedes (the
reinforcement's melt/decomposition bound; ``ablation_surface_temperature``). The gas-side
load at that temperature comes from engine.pipeline.thermal.gas_side (Bartz convection,
H2O/CO2 gas radiation), station by station. The mass consumed follows the quasi-steady
(Landau) balance

    q_net = m'' * [H_abl + cp * (T_s - T_init)]

the heat of ablation plus the sensible heat to bring virgin liner from its initial
temperature to the surface. Pyrolysis gas thickens the boundary layer: convection is
reduced by f(B) = 1/(1 + c B), B the pyrolysis flow over the chamber flow, or by the
legacy constant (1 - blowing_efficiency) when physics blowing is off.

The hot face exchanges radiation with the gas only; the gas term is net of the wall's own
emission, so nothing more is subtracted (an internal liner does not see the room).

Function Documentation

ablation_energy_per_mass()

float engine.pipeline.thermal.ablative_cooling.ablation_energy_per_mass	(	AblativeCoolingConfig	cfg,
		float	surface_temperature )

J per kg of liner consumed at a surface held at ``surface_temperature``.

Definition at line 30 of file ablative_cooling.py.

References max.

Referenced by liner_response().

blowing_reduction()

float engine.pipeline.thermal.ablative_cooling.blowing_reduction	(	AblativeCoolingConfig	cfg,
		float	pyrolysis_mdot,
		Optional[float]	gas_mdot )

Fraction of the convective flux left after pyrolysis-gas blowing.

Definition at line 35 of file ablative_cooling.py.

References max.

Referenced by liner_response().

liner_response()

Dict[str, object] engine.pipeline.thermal.ablative_cooling.liner_response	(		gas,
			contour,
		AblativeCoolingConfig	cfg,
		float	x_liner_end,
		float	gas_mdot,
		Optional[float]	surface_temperature = None,
		bool	with_profile = False )

Quasi-steady ablation of the liner from the face to ``x_liner_end`` (throat frame).

``gas`` is a gas_side.HotGasState and ``contour`` a gas_side.WallContour. Returns the
barrel-station numbers under the old keys (recession_rate, heat_flux_from_gas_*), the
peak along the liner, the integrated heat to the liner, and with ``with_profile`` the
whole-contour display arrays (segment_*).

Definition at line 45 of file ablative_cooling.py.

References ablation_energy_per_mass(), blowing_reduction(), and max.