Superorbital Entry Research Articles

Calculation of Heat Loads in Analysis of Superorbital Entry of Spacecraft into Atmosphere of the Earth

Calculation of Heat Loads in Analysis of Superorbital Entry of Spacecraft into Atmosphere of the Earth

The Radiative Gas Dynamics of a Descent Space Capsule under Conditions of Orbital and Superorbital Entry into the Earth’s Atmosphere

The Radiative Gas Dynamics of a Descent Space Capsule under Conditions of Orbital and Superorbital Entry into the Earth’s Atmosphere

Spatial Problem of the Aerophysics of a Superorbital Space Vehicle at High Altitudes

The spatial problem of the aerophysics of a superorbital entry of the Apollo-4 command module into the dense layers of the Earth’s atmosphere at an angle of attack of 25°, an entry velocity V∞ = 10.7 km s–1, and altitudes of 91.5 and 76.2 km has been solved. The distributions of the spectral and integral radiative heat flux densities along the entire streamlined surface have been derived. A significant role of the electronic bands of diatomic molecules in the radiative heating of the surface has been shown.

Three-Dimensional Problem of Radiative Gasdynamics of the Apollo-4 Command Module during Superorbital Atmospheric Entry

The three-dimensional problem of radiative gasdynamics of the superorbital entry of the Apollo-4 command module into the dense terrestrial atmosphere at an angle of attack of 25° is numerically solved. The flow conditions corresponding to the flight velocity V∞ = 10.5 km/s at an altitude H = 67.3 km are considered in detail. The distributions of the densities of convective and radiative heat fluxes along the surface in a flow are obtained. The spectral composition of the thermal radiation attaining the surface is studied. The results of the calculations are successfully compared with the data of two-dimensional calculations.

Nonequilibrium Radiation Aerothermodynamics of the Command Modulus of Apollo 4 at Altitudes above 75 km

The problem of the radiation gas dynamics of super-orbital entry into dense layers of the Earth’s atmosphere of the command module of Apollo 4 is solved numerically in the two-dimensional formulation of the flow around an aerodynamic frontal shield at the velocity V∞= 10.7 km/s in the altitude range H = 91.5‒76.2 km. The density distributions of the spectral and integral radiation heat fluxes on the surface flowed around are obtained. The considerable role of atomic spectral lines in the radiation heating of the surface is shown. The results of calculations are compared with the flight experimental data and the calculated data of other authors.

Radiative gasdynamics of the nose surface of the Apollo-4 command module at its superobrital reentry

The problem of the radiative gasdynamics of the Apollo-4 command module superorbital entry in the dense terrestrial atmosphere is numerically solved in the two-dimensional formulation of flow past an aerodynamic nose shield on the entry velocity range V∞ = 10.7−5.75 km/s and the altitude range H = 91.5−35.0 km. The specific regions of the trajectory with strongly nonequilibrium flow in the shock layer, the most high-heat areas of the trajectory, and the regions with strong radiative-gasdynamic interaction in a relatively dense and strongly rarefied oncoming flow are highlighted. The density distributions of the convective and radiative heat fluxes over the body surface are obtained. The spectral composition of the thermal radiation is studied. The results of the calculations are compared and found to be in good agreement with the experimental flight data.

Numerical solution of near-equilibrium boundary layers.

2 Alien, R. A., Graphs: Spectrally Integrated Fluxes Including Line Contributions and Self Absorption, CR-556, Aug. 1966, NASA. 3 Gruszczynski, J. S. and Warren, W. R., Study of Equilibrium Air Total Radiation, AIAA Journal, Vol. 5, No. 3, March 1967, pp. 517-525. 4 Hunt, B. L. and Sibulkin, M., Transfer in a Gas of Uniform Properties in Local Thermodynamic Equilibrium Part 3: Detailed Calculation for Nitrogen, Nonr-562(35)/18, Dec. 1966, Brown Univ., Providence, R.L 5 Callis, L. B., Time Asymptotic Solutions of Blunt Body Stagnation Region Flows with Nongray Emission and Absorption of Radiation, TR, NASA (to be published). 6 Hoshizaki, H. and Wilson, K. H., Convective and Radiative Heat Transfer During Superorbital Entry, CR-584, Sept. 1966, NASA. 7 Chin, J. H., Effects of Non-Grey Self-Absorption and Energy Loss for Blunt-Body Flows, Journal of Quantitative Spectroscopy & Transfer, Vol. 8, 1968, pp. 503-511. 8 Thomas, M., Radiation Transfer Through High-Temperature Shock Layers, Paper 68-788, 1968, AIAA. 9 Suttles, J. T., A Method of Integral Relations Solution to the Non-Adiabatic Problem for an Inviscid BluntBody Flow Field, M.S. thesis, March 1968, Virginia Polytechnic Institute, Blacksburg, Va. 10 Suttles, J. T., private communication, May 1968. 11 Wilson, K. H., RATRAP-A Transport Code, March 1967, Lockheed Missile & Space Co. 12 Page, W. A. et al., Transport in Inviscid Nonadiabatic Stagnation-Region Shock Layers, Paper 68-784, 1968, AIAA. 13 Callis, L. B., private communication, May 1968.

Effect of shock precursor absorption on superorbital entry heating.

Quantitative determination of reentry shock precursor absorption level and effect on surface radiation heating, calculating radiative flux from shock layer enthalpy distribution

Fast-Response Total Thermal Radiation Detectors

The construction, calibration, and performance of thin-film heat-transfer gauges in a measurement of the total radiant intensity of air at superorbital entry conditions are discussed. It is shown that reliance on an electrical bridge calibration alone can cause erroneous results. Magnetic interference from the shock tube flow was identified and eliminated by model design and shielding. Thin-film gauges are shown to be fundamentally unsuited for total radiation measurements because of noise caused by vacuum ultraviolet irradiation. Pyroelectric thermal detectors avoid this difficulty and offer several other advantages over thin-film gauges. The basic equations and practical considerations in the use of pyroelectric gauges are discussed.

Convective and radiative heat transfer during superorbital entry.

Convective and radiative heat transfer to space vehicles entering planetary atmospheres at superorbital velocities