Crate hpr_aero 

Aerodynamics: Barrowman normal force and center of pressure with extensions, drag buildup, compressibility and override tables.

Guide: Aerodynamics: the models, their sources, how well they are validated and what they leave out.

• body: nose cones, body tubes and transitions: Barrowman’s slope and center of pressure.
• crossflow: body lift, the crossflow’s push on a body at an angle of attack: Jorgensen’s η C_dn against the body’s fineness and the crossflow Mach number, or Galejs’s constant.
• fins: fin sets: Barrowman’s slope with Prandtl–Glauert, the mean aerodynamic chord, supersonic linear theory and the transonic join between them, fin-count and roll terms, and fin–body interference.
• drag: the terms of Niskanen’s zero-lift drag buildup, and axial drag at an angle of attack.
• nose_drag: the pressure drag of noses, shoulders and steps from rest through Mach 1 to supersonic speeds, with Stoney’s measured curves.
• afterbody: a boattail’s wave drag faster than sound, and the base pressure behind it.
• shock_expansion: the second-order shock-expansion method for a pointed body faster than sound (NACA TN 3527).
• supersonic_boattail: a boattail’s measured share of the normal force faster than sound (Washington and Pettis, RD-TM-68-5).
• table: override tables from another tool: the drag coefficient against Mach number, and the normal force and center of pressure against Mach number and angle of attack, read from RASAero II’s export.
• tube_fins: tube fins, each tube an annular wing: Weissinger’s slope with Göthert’s rule, Fletcher’s measured aerodynamic center, below Mach 0.8.
• custom: drag models of your own: the DragModel trait, flown in place of the drag buildup.
• model: a rocket’s terms built from a hpr_design::Layout and summed at a Flow.

A rocket’s center of pressure is NormalForce::cp_station_m, in meters aft of the nose tip, from AeroModel::normal_force at Flow::axial (Your rocket’s center of pressure in the guide).

Status: the normal force and center of pressure from Mach 0 to 5 (fins through the transonic region to supersonic linear theory, Fins through Mach 1); the drag buildup from Mach 0 to 5 (noses, shoulders and steps through Mach 1 by Niskanen’s appendix B, Drag through Mach 1); drag override tables, and drag models of a program’s own (custom), at any Mach number; normal-force override tables from RASAero II’s export (The normal force from RASAero II); the roll forcing of canted fins and the roll damping from Mach 0 to 5 (AeroModel::roll, Roll: forcing and damping).

• Pitch and yaw damping in a flight come only from the flight engine (hpr_sim) evaluating each component in its own local flow, which includes the speed the rocket’s rotation adds there (Rigid-body flight in the guide). The crate has no pitch or yaw damping coefficients; they would have to replace the local-flow damping, not add to it.
• Only components with a normal-force slope give that damping: nose cones, transitions and fin sets. Body tubes give none at small angles: their own slope is 0, and their body lift grows with sin² α.

Re-exports

pub use afterbody::Boattail;

pub use body::BODY_LIFT_K;

pub use body::BodyGeometry;

pub use crossflow::BodyLift;

pub use custom::DragModel;

pub use custom::DragQuery;

pub use drag::BaseBehindBoattail;

pub use drag::BoattailTerm;

pub use drag::ComponentDrag;

pub use drag::ComponentDragTerms;

pub use drag::Drag;

pub use drag::DragConditions;

pub use drag::MOTOR_POD_SETS;

pub use drag::MergedBoattail;

pub use drag::PressureDragTerm;

pub use drag::ReliefSource;

pub use drag::WakeTerm;

pub use error::AeroError;

pub use fins::FinAero;

pub use fins::FinGeometry;

pub use fins::FinLoading;

pub use fins::FinOutline;

pub use fins::FinRoll;

pub use fins::FinRollTerms;

pub use fins::fin_count_factor;

pub use fins::interference_factor;

pub use fins::roll_damping_interference;

pub use fins::roll_forcing_interference;

pub use fins::roll_sum;

pub use fins::side_sum;

pub use model::AeroModel;

pub use model::BodyAero;

pub use model::BodyModel;

pub use model::ComponentNormalForce;

pub use model::FinSetAero;

pub use model::Flow;

pub use model::MAX_CANT_RAD;

pub use model::NORMAL_FORCE_MACH_LIMIT;

pub use model::NormalForce;

pub use model::PodFins;

pub use model::PodSetAero;

pub use model::Roll;

pub use model::SUPERSONIC_JOIN_START_MACH;

pub use model::SUPERSONIC_JOIN_WIDTH_MACH;

pub use model::SupersonicBoattail;

pub use model::SupersonicBody;

pub use model::SupersonicFallback;

pub use model::SupersonicFlare;

pub use nose_drag::PressureDragCurve;

pub use nose_drag::StoneyNose;

pub use table::DragTable;

pub use table::NormalForceColumn;

pub use table::NormalForceLookup;

pub use table::NormalForceTable;

pub use table::TableReference;

pub use table::parse_mach_csv;

pub use tube_fins::TubeFinSetAero;

Modules

afterbody

The afterbody faster than sound: a boattail’s own pressure drag, and the base pressure behind it.

blunt_tip

A blunt or vertical nose tip faster than sound: modified Newtonian pressures on the cap, handed over to the second-order shock-expansion method (crate::shock_expansion) where the surface slope falls to the steepest wedge an attached shock can turn. After C. M. Jackson Jr., W. C. Sawyer and R. S. Smith, A Method for Determining Surface Pressures on Blunt Bodies of Revolution at Small Angles of Attack in Supersonic Flow, NASA TN D-4865 (1968) (J68).

body

Bodies of revolution (nose cones, body tubes, transitions): Barrowman’s normal-force slope and center of pressure, and the planform body lift acts on.

crossflow

Body lift: the viscous crossflow term of Jorgensen’s method for bodies of revolution at an angle of attack (L. H. Jorgensen, NASA TR R-474, 1977), and Galejs’s constant it replaces.

custom

Drag models of your own, flown in place of hpr’s drag buildup.

drag

Drag: the terms of Niskanen’s zero-lift drag buildup and the angle-of-attack scaling of axial drag, as functions of their inputs. crate::AeroModel::drag sums them over a rocket.

error

Error types for the aerodynamic models.

fins

Fin sets: Barrowman’s subsonic normal-force slope and center of pressure, with the Prandtl–Glauert factor; supersonic linear theory and the transonic join between them (FinAero); the fin-count and roll terms, and fin–body interference.

model

A rocket’s normal force and center of pressure: every component’s terms, built once from a Layout and summed at each flow condition.

nose_drag

Pressure drag of noses, shoulders and steps at every Mach number: Niskanen’s semi-empirical method (2009 §3.4.3, eq. 3.86–3.87, and appendix B), with Stoney’s measured curves for the shapes that have no closed form.

shock_expansion

The normal force of a pointed body of revolution faster than sound, by Syvertson and Dennis’s second-order shock-expansion method (NACA TN 3527, 1956, also NACA Report 1328).

supersonic_boattail

A conical boattail’s share of the normal force faster than sound, measured: W. D. Washington and W. Pettis Jr., Boattail Effects on Static Stability at Small Angles of Attack, U.S. Army Missile Command report RD-TM-68-5 (1968; DTIC AD-695658, approved for public release).

table

Override tables: coefficients from another tool or a measurement in place of hpr’s own.

tube_fins

Tube fins: a ring of short open tubes around the body, each flown as an annular wing (a ring airfoil).