Struct WakeTerm 

#[non_exhaustive]
pub struct WakeTerm {
    pub boattail: Boattail,
    pub step_fraction: f64,
    pub shoulder_fraction: f64,
}

A lip in a boattail’s wake: its step up’s pressure drag is scaled by 1 − step_fraction and its shoulder’s by 1 − shoulder_fraction.

NASA’s Arcas Robin models end in a lip 1.3 mm long, rising 0.17 of the boattail’s drop, whose effect TN D-4014 finds “masked” when the flow over the boattail separates or the boundary layer thickens (Babb and Fuller 1967, p. 6), and which RASAero II’s own comparison with the tunnel left out as “buried in the boattail boundary layer” (Rogers 2022, slide 2). A flare back toward the body’s full diameter is a compression surface with a drag of its own. Between the two no source gives a measure, so the fraction is a judgement: 1 while the lip’s top rises no more than WAKE_FULL_RISE of the boattail’s drop in diameter above the boattail’s aft end, 0 from WAKE_NONE_RISE, linear between; and it fades with any tube, step down or part between them over one drop in diameter. A lip may be drawn as a shoulder, as a step up, or as both, and in several parts: each takes the smallest share any top so far leaves, its step by its fore radius and its shoulder by its aft radius too. With several boattails ahead, each contributes its share of the flow; the fractions are summed and capped at 1. A step down counts as a boattail of no length, so a lip behind a plain step, such as a motor retainer behind the step down to the motor tube, is in its wake too.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

boattail: Boattail

The boattail ahead that holds the most of the flow: a narrowing part’s own, the cone of the surface it continues, or a step down’s corner, a boattail of no length.

step_fraction: f64

How much of a step up’s pressure drag at the lip’s fore end the wake removes, from 0 to 1.

shoulder_fraction: f64

How much of the lip’s shoulder’s pressure drag the wake removes, from 0 to 1.

Trait Implementations

impl Clone for WakeTerm

fn clone(&self) -> WakeTerm

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for WakeTerm

impl Debug for WakeTerm

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for WakeTerm

fn eq(&self, other: &WakeTerm) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for WakeTerm

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for WakeTerm