Scenario kind pagesEdit on GitHubSource: docs/kinds/by-kind/entry-heating.md

entry-heating (scenario kind)

Scenario kind of the engine v0.38.0, family Mission analysis, links and space operations. Advisory: analysis output from a research and engineering tool, not type-approved navigation equipment and not a safety-of-life service. Every label here is the engine's or the verification matrix's; a kind is MODELLED unless the matrix says otherwise (how a label is earned: the README's Evidence section).

What it does#

3-DoF point-mass atmospheric entry over a rotating spherical Earth or Mars (ballistic or lifting at constant bank), RK4, through US76, an exponential or the Mars atmosphere, with Sutton-Graves stagnation-point convective heating (NASA TR R-376): peak deceleration, heat flux and dynamic pressure, heat load, downrange, a rotating-frame energy check and the Allen-Eggers closed form beside it. Peak deceleration is checked against the published Stardust nominal; heating is MODELLED.

One run of scenarios/entry-heating-stardust.toml summarises as: entry-heating (earth): V_rel 12551 m/s, γ 8.43° -> peak 35.4 g at 54.2 km, peak q 746 W/cm² at 62.0 km, heat load 20970 J/cm², peak q_dyn 20.8 kPa; terminal-altitude at 317 s (closed form 60.2 g; MODELLED 3-DoF, no radiative/TPS)

Inputs#

From the schema (kshana kinds --json):

  • Required fields: none
  • Optional fields: body, atmosphere, rho0_kg_m3, scale_height_m, entry_interface_altitude_m, velocity_frame, entry_speed_m_s, flight_path_angle_deg, heading_deg, latitude_deg, longitude_deg, mass_kg, drag_coefficient, reference_area_m2, nose_radius_m, lift_to_drag, bank_angle_deg, rotating_planet, step_s, terminal_altitude_m, max_time_s

The example scenarios/entry-heating-stardust.toml sets, among others:

Field Value Unit
atmosphere us76 text
body earth text
drag_coefficient 1.4828 1
entry_interface_altitude_m 125003 m
entry_speed_m_s 12900 m/s
flight_path_angle_deg 8.2 deg
heading_deg 100 deg
kind entry-heating text
latitude_deg 41 deg
lift_to_drag 0 1
mass_kg 45.8 kg
nose_radius_m 0.2202 m

Run it#

kshana scenarios/entry-heating-stardust.toml

What it gives#

The scalar results of that run, with the units the engine states:

Result Value Unit
atmosphere US Standard Atmosphere 1976 text
ballistic_coefficient_kg_m2 59.793465 kg/m^2
body earth text
closed_form_check.altitude_at_peak_m 49780.760635 m
closed_form_check.integrated_over_closed_form 0.589074 1
closed_form_check.peak_deceleration_g 60.160557 1
closed_form_check.reference NACA Report 1381 (1958) ballistic consta text
closed_form_check.rho0_kg_m3 1.225 kg/m^3
closed_form_check.scale_height_m 7200 m
energy_check.residual 9.5628e-13 1

Result label (the engine's): MODELLED — 3-DoF point-mass entry over a rotating spherical planet (central gravity, no J2), co-rotating windless atmosphere, constant C_D, L/D and bank, RK4; convective stagnation-point heating per NASA TR R-376 (1971), cold wall, NO radiative heating, NO TPS/ablation response, NOT 6-DoF

The chart the engine writes for scenarios/entry-heating-stardust.toml, kind entry-heating

Evidence#

MODELLED 1 · VALIDATED 1: the verification matrix rows that name this kind.

  • VALIDATED A 3-DoF point-mass entry over a rotating spherical Earth through the US Standard Atmosphere 1976, integrated with RK4 from an inertial entry state, reporting the peak deceleration and its altitude; the planet-relative entry state from the i Tests: entry_stardust_published.rs.
  • MODELLED Stagnation-point convective heat flux q = k sqrt(rho/R_n) V^3 with the Sutton-Graves constants for Earth air and the Mars atmosphere (NASA TR R-376, 1971), its peak and the integrated heat load along a 3-DoF entry, ballistic or lifting at c Tests: entry_stardust_published.rs.

The rows the run itself exercised, with the oracle the matrix gives each (the public sources are named there):

  • MODELLED Deterministic, scenario-hashed, SBOM + cross-platform golden gates. Oracle (ExternalDataset): SBOM conformance to the official CycloneDX 1.5 JSON Schema (+ valid SPDX identifiers) — an external published standard, zero validation errors over the full dependency graph; the FoM-determinism / byte-reproducibility part remains a pinned self-consistency check, so the row stays MODELLED
  • VALIDATED A 3-DoF point-mass entry over a rotating spherical Earth through the US Standard Atmosphere 1976, integrated with RK4 from an inertial entry state, reporting th. Oracle (ExternalDataset): The Stardust nominal of Desai, Mitcheltree and Cheatwood (1999, NASA NTRS 20050042027): maximum deceleration 33.4 g from 12.6 km/s planet-relative with the 45.8 kg launch mass, a 6-DoF POST trajectory with the full aerodynamic database; entry interface from Desai, Lyons, Tooley and Kangas (NTRS 20090004445): radius 6503.14 km, inertial 12.9 km/s at -8.2 deg. Bars pre-registered in xval/entry-stardust/PREREGISTRATION.
  • MODELLED Stagnation-point convective heat flux q = k sqrt(rho/R_n) V^3 with the Sutton-Graves constants for Earth air and the Mars atmosphere (NASA TR R-376, 1971), its . Oracle (InternalConsistency): Internal consistency: the relation and constants as printed in NASA TR R-376, a half-step convergence check, and the expected ordering of heating and deceleration peaks. WHAT IS NOT: no published heating value has been compared (the Stardust papers give a design limit and a convective-plus-radiative estimate of about 1200 W/cm2, which a convective-only relation cannot match); no radiative heating, wall-temperature or

Limitations#

What the run's own report says is not modelled or not validated:

  • MODELLED — 3-DoF point-mass entry over a rotating spherical planet (central gravity, no J2), co-rotating windless atmosphere, constant C_D, L/D and bank, RK4; convective stagnation-point heating per NASA TR R-376 (1971), cold wall, NO radiative heating, NO TPS/ablation response, NOT 6-DoF (result label)
  • Peak deceleration is checked against the published Stardust nominal; heating is MODELLED. (kind catalogue (kshana kinds --json))
  • Entry interface at a radius of 6503.14 km, inertial 12.9 km/s at -8.2 deg, 45.8 kg, 0.811 m diameter, 0.2202 m nose radius (Desai et al., NASA NTRS 20050042027 and 20090004445). The latitude and heading are an assumed approximate entry over the Pacific; C_D is the module's 60 deg sphere-cone default. Published 6-DoF nominal peak deceleration: 33.4 g. The heating is Sutton-Graves convective only, MODELLED. (scenario file comment, lines 4 to 8)
  • Reproducibility & software assurance is MODELLED, not validated: a sub-claim is externally checked, but the whole capability composes modelled pieces, so the capability stays Modelled. (verification matrix (docs/MODELLED-RATIONALE.md))
  • Stagnation-point convective entry heating (Sutton-Graves) on a 3-DoF entry is MODELLED, not validated: checked against its own closed-form / analytic identity — catches transcription and coefficient errors, but is not an external oracle. (verification matrix (docs/MODELLED-RATIONALE.md))

See also#