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Johnson, C. B.

Publications and source records attributed to Johnson, C. B..

71 records · Page 4

Chemical nonequilibrium effects on the flow in the windward plane of symmetry of a blunted delta orbiter

The extent, and some of the consequences, of nonequilibrium effects in the inviscid orbiter flow field are examined. Calculations have been made for the reacting flow along selected streamlines in the windward plane of symmetry of a blunted delta shape representative of a shuttle orbiter. An approximate model of the pressure field in the windward plane of symmetry of a blunted delta wing was constructed from wind tunnel measurements of the body surface pressure distribution and approximate calculations of the shock shape and streamline locations. Numerical solutions for the flow along streamlines were obtained for this pressure distribution, and solutions were obtained for both equilibrium and finite-reaction rate, nonequilibrium chemical reactions. Since the streamtube solutions are much easier to compute than fully three-dimensional, reacting flows, results were obtained for a wide range of conditions. The validity of this approach is based on the assumptions that the pressure field is insensitive to nonequilibrium effects and that the flow along streamlines is quasi-one dimensional. Numerical solutions have been used to verify this approach for other blunted slender shapes such as spherically blunted cones.

Lordi, J. A.↗

High Reynolds number turbulent heating to two simplified shuttle configurations

Turbulent heating and transition data, taken from three test facilities, for two space shuttle configurations are presented. Major efforts were on: (1) the effect of the two geometries having different amounts of cross flow and how the different cross flows affect heating and transition, (2) the experimental level of turbulent heating and the ability to predict the level of turbulent heating, and (3) a comparison of the transitional and turbulent heating in three facilities with two model scale sizes to investigate the facility effects and scale-size effect on transition and turbulent heating. The three facilities in which the configurations were tested are the Langley Mach 8 variable-density hypersonic tunnel and the Arnold Engineering Development Center tunnel B and tunnel F at Mach numbers of 8 and 10.5, respectively.

Johnson, C. B.↗

A study of optical image sensors for the large space telescope.

A generalized approach is attempted to the problem of designing an image sensor that is to be used on a large spaceborne telescope. General design and performance goals are presented, and the parameters describing the sensor characteristics are discussed. Electrooptical techniques and components presently available are reviewed, and promising design orientations are explored.

Hallam, K. L.↗

Hypersonic test facility Patent

Design of hypersonic test facility for ablation tests and performance tests of vehicles under conditions of high temperature and pressure

Buchanan, R. I.↗

Recent Work at Langley Research Center in the Development of a Graphite-Heated Small-Scale Hypersonic Nitrogen Tunnel

It is the purpose of this paper to discuss the development of and to present some preliminary data results which were obtained during the operation of a high-pressure-high-temperature induction-type heat exchanger. The subjects to be covered are: (1) An overall description of the induction heater and the various graphite elements tested in the heater; (2) Effects of the mass rate of flow on stagnation temperature; (3) Heat-transfer data on one heater element; (4) Effect of power input on gas stagnation temperature, and (5) The evaluation of mass flow technique as a method for determining true gas stagnation temperature.

HEAT EXCHANGER↗