Differences between revisions 4 and 5
Revision 4 as of 2016-12-06 23:39:44
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Revision 5 as of 2016-12-06 23:41:58
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 . 1a: $ \dot Q_c = 20 \rho^{1/2} \left( V \over 1000 \right)^3$ Btu/ft^2^-s  . 1a: $ \dot Q_c = 20 \rho^{1/2} \left( V \over 1000 \right)^3$ Btu/ft^2^-s convective power
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 . 1b: $ \dot Q_r = 6.1 \rho^{3/2} \left( V \over { 10 000 } \right)^{20} $ Btu/ft^2^-s  . 1b: $ \dot Q_r = 6.1 \rho^{3/2} \left( V \over { 10 000 } \right)^{20} $ Btu/ft^2^-s radiative power
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 . Metric 1a: $ \dot Q_c = $3.53e-4$ \rho^{1/2} V^3 $  . Metric 1a: $ \dot Q_c = $ 3.53e-4 $ \rho^{1/2} V^3 $
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 . Metric 1b: $ \dot Q_r = $3.32e-71$ \rho^{3/2} V^{20} $  . Metric 1b: $ \dot Q_r = $ 3.32e-71 $ \rho^{3/2} V^{20} $

Hypervelocity Drag

Based on Trajectory Optimization for an Apollo-type Vehicle under Entry Conditions Encountered During Lunar Returm by John W. Young (famous astronaut) and Robert E. Smith Jr., May 1967, NASA TR-R-258, Langley Research Center.

Equations on Page 5 in Foot-second-slug-BTU :

  • 1a: \dot Q_c = 20 \rho^{1/2} \left( V \over 1000 \right)^3 Btu/ft2-s convective power

  • 1b: \dot Q_r = 6.1 \rho^{3/2} \left( V \over { 10 000 } \right)^{20} Btu/ft2-s radiative power

  • Equations assume an effective nose radius of 1 foot
  • Equations from Shock Layer Radiation During Hypervelocity Re-Entry by Robert M. Nerem and George H. Stickford, AIAA Entry Technology Conference, CP-9, American Institute of Aeronautics and Astronautics, Oct. 1964, pp 158-169.

Density in slugs/ft3: multiply kg/m3 by 1.9403203e-3

Power in Btu/ft2-s: multiply by 11350.54 to get W/m2

Velocity in ft/s: divide m/s by 0.3048

Metric equations:

  • Metric 1a: \dot Q_c = 3.53e-4 \rho^{1/2} V^3

  • Metric 1b: \dot Q_r = 3.32e-71 \rho^{3/2} V^{20}

HypervelocityDrag (last edited 2017-03-01 00:19:49 by KeithLofstrom)