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Corrected atmosphere data, extended above 62000ft

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Author: John Denker
Reviewed by: Ron Jensen and Gerard Robin
This commit is contained in:
timoore 2007-08-31 18:01:07 +00:00
parent a408d248ad
commit 24173c0398
1 changed files with 42 additions and 35 deletions
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77
src/Environment/environment.cxx
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@ -49,43 +49,50 @@
// Atmosphere model. // Atmosphere model.
//////////////////////////////////////////////////////////////////////// ////////////////////////////////////////////////////////////////////////
// Copied from YASim Atmosphere.cxx, with m converted to ft, degK // Calculated based on the ISA standard day, as found at e.g.
// converted to degC, Pa converted to inHG, and kg/m^3 converted to // http://www.av8n.com/physics/altimetry.htm
// slug/ft^3; they were then converted to deltas from the sea-level
// defaults (approx. 15degC, 29.92inHG, and 0.00237slugs/ft^3).
// Original comment from YASim: // Each line of data has 3 elements:
// Elevation (ft),
// Copied from McCormick, who got it from "The ARDC Model Atmosphere" // temperature factor (dimensionless ratio of absolute temp),
// Note that there's an error in the text in the first entry, // pressure factor (dimensionless ratio)
// McCormick lists 299.16/101325/1.22500, but those don't agree with
// R=287. I chose to correct the temperature to 288.20, since 79F is
// pretty hot for a "standard" atmosphere.
// Elevation (ft), temperature factor (degK), pressure factor (inHG)
static double atmosphere_data[][3] = { static double atmosphere_data[][3] = {
{ 0.00, 1.00, 1.000 }, { -3000.00, 1.021, 1.1133 },
{ 2952.76, 0.98, 0.898 }, { 0.00, 1.000, 1.0000 },
{ 5905.51, 0.96, 0.804 }, { 2952.76, 0.980, 0.8978 },
{ 8858.27, 0.94, 0.719 }, { 5905.51, 0.959, 0.8042 },
{ 11811.02, 0.92, 0.641 }, { 8858.27, 0.939, 0.7187 },
{ 14763.78, 0.90, 0.570 }, { 11811.02, 0.919, 0.6407 },
{ 17716.54, 0.88, 0.506 }, { 14763.78, 0.898, 0.5697 },
{ 20669.29, 0.86, 0.447 }, { 17716.54, 0.878, 0.5052 },
{ 23622.05, 0.84, 0.394 }, { 20669.29, 0.858, 0.4468 },
{ 26574.80, 0.82, 0.347 }, { 23622.05, 0.838, 0.3940 },
{ 29527.56, 0.80, 0.304 }, { 26574.80, 0.817, 0.3463 },
{ 32480.31, 0.78, 0.266 }, { 29527.56, 0.797, 0.3034 },
{ 35433.07, 0.76, 0.231 }, { 32480.31, 0.777, 0.2649 },
{ 38385.83, 0.75, 0.201 }, { 35433.07, 0.756, 0.2305 },
{ 41338.58, 0.75, 0.174 }, { 38385.83, 0.752, 0.2000 },
{ 44291.34, 0.75, 0.151 }, { 41338.58, 0.752, 0.1736 },
{ 47244.09, 0.75, 0.131 }, { 44291.34, 0.752, 0.1506 },
{ 50196.85, 0.75, 0.114 }, { 47244.09, 0.752, 0.1307 },
{ 53149.61, 0.75, 0.099 }, { 50196.85, 0.752, 0.1134 },
{ 56102.36, 0.75, 0.086 }, { 53149.61, 0.752, 0.0984 },
{ 59055.12, 0.75, 0.075 }, { 56102.36, 0.752, 0.0854 },
{ 62007.87, 0.75, 0.065 }, { 59055.12, 0.752, 0.0741 },
{ 62007.87, 0.752, 0.0643 },
{ 65000.00, 0.752, 0.0557 },
{ 68000.00, 0.754, 0.0482 },
{ 71000.00, 0.758, 0.0418 },
{ 74000.00, 0.761, 0.0362 },
{ 77000.00, 0.764, 0.0314 },
{ 80000.00, 0.767, 0.0273 },
{ 83000.00, 0.770, 0.0237 },
{ 86000.00, 0.773, 0.0206 },
{ 89000.00, 0.777, 0.0179 },
{ 92000.00, 0.780, 0.0156 },
{ 95000.00, 0.783, 0.0135 },
{ 98000.00, 0.786, 0.0118 },
{ 101000.00, 0.789, 0.0103 },
{ -1, -1, -1 } { -1, -1, -1 }
}; };