Engineering topics

Stephenson, J. G.

Publications and source records attributed to Stephenson, J. G..

4 records

NASA NTRS1985

Insulating Cryogenic Pipes With Frost

Crystallized water vapor fills voids in pipe insulation. Small, carefully controlled amount of water vapor introduced into dry nitrogen gas before it enters aft fuselage. Vapor freezes on pipes, filling cracks in insulation. Ice prevents gaseous nitrogen from condensing on pipes and dripping on structure, in addition to helping to insulate all parts. Industrial applications include large refrigeration plants or facilities that use cryogenic liquids.

Stephenson, J. G.↗

NASA NTRS1983

Measuring Small Leak Holes

Hole sizes deduced from pressure measurements. Measuring apparatus consists of pitot tube attached to water-filled manometer. Compartment tested is pressurized with air. Pitot probe placed at known distance from leak. Dynamic pressure of jet measured at that point and static pressure measured in compartment. Useful in situations in which small leaks are tolerable but large leaks are not.

Koch, D. E.↗

NASA NTRS1982

Three-Dimensional Air Curtains

Proposed scheme for gas "curtains" partitions large volume into several separate spaces. Concept may also be useful in such terrestrial applications as unobtrusive isolation of smoking and nonsmoking sections in restaurants and office. Scheme is suitable for isolation of objectionable or hazardous gases in free space.

Stephenson, J. G.↗

NASA NTRS1978

Improved dewpoint-probe calibration

Relatively-simple pressure-control apparatus calibrates dewpoint probes considerably faster than conventional methods, with no loss of accuracy. Technique requires only pressure measurement at each calibration point and single absolute-humidity measurement at beginning of run. Several probes can be calibrated simultaneously and points can be checked above room temperature.

Stephenson, J. G.↗