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Kelly, H. N.

Publications and source records attributed to Kelly, H. N..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Modification to the Langley 8-foot high temperature tunnel for hypersonic propulsion testing

Described are the modifications currently under way to the Langley 8-Foot High Temperature Tunnel to produce a new, unique national resource for testing hypersonic air-breathing propulsion systems. The current tunnel, which has been used for aerothermal loads and structures research since its inception, is being modified with the addition of a LOX system to bring the oxygen content of the test medium up to that of air, the addition of alternate Mach number capability (4 and 5) to augment the current M=7 capability, improvements to the tunnel hardware to reduce maintenance downtime, the addition of a hydrogen system to allow the testing of hydrogen powered engines, and a new data system to increase both the quantity and quality of the data obtained.

Reubush, D. E.↗
NASA NTRS1984

Shell tile thermal protection system

A reusable, externally applied thermal protection system for use on aerospace vehicles subject to high thermal and mechanical stresses utilizes a shell tile structure which effectively separates its primary functions as an insulator and load absorber. The tile consists of structurally strong upper and lower metallic shells manufactured from materials meeting the thermal and structural requirements incident to tile placement on the spacecraft. A lightweight, high temperature package of insulation is utilized in the upper shell while a lightweight, low temperature insulation is utilized in the lower shell. Assembly of the tile which is facilitated by a self-locking mechanism, may occur subsequent to installation of the lower shell on the spacecraft structural skin.

Macconochie, I. O.↗
NASA NTRS1984

Modification of NASA Langley 8 foot high temperature tunnel to provide a unique national research facility for hypersonic air-breathing propulsion systems

A planned modification of the NASA Langley 8-Foot High Temperature Tunnel to make it a unique national research facility for hypersonic air-breathing propulsion systems is described, and some of the ongoing supporting research for that modification is discussed. The modification involves: (1) the addition of an oxygen-enrichment system which will allow the methane-air combustion-heated test stream to simulate air for propulsion testing; and (2) supplemental nozzles to expand the test simulation capability from the current nominal Mach number to 7.0 include Mach numbers 3.0, 4.5, and 5.0. Detailed design of the modifications is currently underway and the modified facility is scheduled to be available for tests of large scale propulsion systems by mid 1988.

Kelly, H. N.↗
NASA NTRS1984

Modification of NASA Langley 8 Foot High Temperature Tunnel to provide a unique national research facility for hypersonic air-breathing propulsion systems

A planned modification of the NASA Langley 8-Foot High Temperature Tunnel to make it a unique national research facility for hypersonic air-breathing propulsion systems is described, and some of the ongoing supporting research for that modification is discussed. The modification involves: (1) the addition of an oxygen-enrichment system which will allow the methane-air combustion-heated test stream to simulate air for propulsion testing; and (2) supplemental nozzles to expand the test simulation capability from the current nominal Mach number to 7.0 include Mach numbers 3.0, 4.5, and 5.0. Detailed design of the modifications is currently underway and the modified facility is scheduled to be available for tests of large scale propulsion systems by mid 1988.

Kelly, H. N.↗
NASA NTRS1983

Shell-Tile Thermal-Protection System

Durable shell-tile thermal-protection system consists of interlocking upper and lower hard caps, incorporating appropriate stiffeners and enclosing lightweight fibrous insulation. New shell tile more durable than reusable surface insulation (RSI) currently used on Space Shuttle orbiter.

Macconochie, I. O.↗
NASA NTRS1982

Assessment of alternate thermal protection systems for the Space Shuttle Orbiter

Technical aspects of the alternate thermal protection system (TPS) study for the Shuttle Orbiter are reviewed, and a status report on alternate TPS technology developments is presented. Mission impact, life cycle costs and risks, and selected candidate concepts are identified. The best system would consist of mechanically attached metallic and carbon-carbon TPS concepts employing a titanium multiwall prepackaged concept at temperatures below 1000 F, a superalloy honeycomb prepackaged concept at temperatures between 1000-1800 F, and an advanced carbon-carbon multipost standoff concept above 1800 F. Alternative concepts offer significant improvements in durability and are mass competitive with current ceramic tile reusable surface insulation.

Kelly, H. N.↗
NASA NTRS1982

Assessment of Alternate Thermal Protection Systems for the Space Shuttle Orbiter

Candidate concepts are identified. The impact on the Shuttle Orbiter performance life cycle cost, and risk was assessed and technology advances required to bring the selected TPS to operational readiness are defined. The best system is shown to be a hybrid blend of metallic and carbon-carbon TPS concepts. These alternate concepts offer significant improvements in reusability and are mass competitive with the current ceramic tile reusable surface insulation. Programmatic analysis indicates approximately five years are required to bring the concepts to operational readiness.

Kelly, H. N.↗
NASA NTRS1982

Flightweight radiantly and actively cooled panel: Thermal and structural performance

A 2- by 4-ft flightweight panel was subjected to thermal/structural tests representative of design flight conditions for a Mach 6.7 transport and to off-design conditions simulating flight maneuvers and cooling system failures. The panel utilized Rene 41 heat shields backed by a thin layer of insulation to radiate away most of the 12 Btu/ft2-sec incident heating. A solution of ethylene glycol in water circulating through tubes in an aluminum-honeycomb-sandwich panel absorbed the remainder of the incident heating (0.8 Btu/sq ft-sec). The panel successfully withstood (1) 46.7 hr of radiant heating which included 53 thermal cycles and 5000 cycles of uniaxial inplane loading of + or - 1200 lfb/in; (2) simulated 2g-maneuver heating conditions and simulated cooling system failures without excessive temperatures on the structural panel; and (3) the extensive thermal/structural tests and the aerothermal tests reported in NASA TP-1595 without significant damage to the structural panel, coolant leaks, or hot-gas ingress to the structural panel.

Shore, C. P.↗
NASA NTRS1981

Multiwall TPS: An emerging concept

The transformation of a titanium multiwall thermal protection system from a conceptual design to a working reality is described. The thermal and structural performance of the basic multiwall concept is analyzed. Radiant heat, wind tunnel, vibration, acoustic, and lightning strike tests are used to verify the performance of multiwall tiles under representative operating conditions. Flat, all titanium multiwall configurations limited to temperature below 810 K are discussed. Curved surface, higher temperature versions of the multiwall are considered. Preliminary mass estimates for advanced multiwall concepts are presented.

Shideler, J. L.↗
NASA NTRS1981

Heat pipes cool probe and sandwich panel

Two concepts integrate heat-pipe technology. Probe with heat-pipe cooled jacket is self-contained, passive, and has no moving parts, unlike conventional air and water cooled probes. It is used in hostile, high temperature environments like wind tunnels and powerplants or on high-speed research and hypersonic cruise vehicles. Heat-pipe sandwich panel combines structural efficiency of sandwich with thermal efficiency of heat-pipe. It is used to eliminate thermal gradients and stresses, minimize thermal distortions, and transfer heat from one face of panel to other.

Camarda, C. J.↗
NASA NTRS1981

Multiwall TPS - An emerging concept

Research on titanium multiwall used for thermal protection is reviewed. Continuing analytical and experimental studies yielding a fundamental understanding of the thermal and structural performance of the basic multiwall concept are presented noting that central to this understanding is a knowledge of the extensional behavior of the dimpled sheets since the thinner flat sheets will buckle and be relatively ineffective in supporting compressive loads. Results from radiant heating, aerothermal, vibration, acoustic and lightning strike tests are described as part of an effort to verify the performance of multiwall tiles under representative operating conditions. Flight tests of a large array of tiles are also planned as part of an orbiter experiments program. The research effort is being extended from flat all-titanium multiwall configurations limited to temperatures below 810 K to curved surfaces and higher temperature versions. Multi-wall concepts are found to offer the durability of metallic systems and to be mass competitive with the insulation system currently used on the Space Shuttle Orbiter.

Shideler, J. L.↗
NASA NTRS1979

Research in structures and materials for future space transportation systems - An overview

The paper provides a review of some of the advances of the past decade in structures and materials that have application to future space transportation systems. The paper concentrates on metallic thermal protection systems and structures which could provide the structural efficiency, reliability, and durability dictated by future space utilization requirements. The need for completely reusable, on-board cryogenic fuel tanks is cited as the most challenging technical opportunity and potential thermostructural concepts for tanks are identified. Other critical areas needing technology advances are discussed. Finally, the unique research opportunities offered by the Shuttle Orbiter experiments program for testing structures and thermal protection systems are explored.

Kelly, H. N.↗
NASA NTRS1978

Recent advances in convectively cooled engine and airframe structures for hypersonic flight

A hydrogen-cooled structure for a fixed-geometry, airframe-integrated scramjet is described. The thermal/structural problems, concepts, design features, and technological advances are applicable to a broad range of engines. Convectively cooled airframe structural concepts that have evolved from an extensive series of investigations, the technology developments that have led to these concepts, and the benefits that accrue from their use are discussed.

Kelly, H. N.↗
NASA NTRS1978

Recent advances in convectively cooled engine and airframe structures for hypersonic flight

Research over the past decade has identified critical thermal/structural design problems and has produced viable design concepts for a second generation experimental scramjet. The design concepts for the hydrogen fuel-cooled engine structure involve a variety of innovative features to accommodate the harsh aerothermal environment encountered within the engine. The baseline concept which has evolved has reasonable mass characteristics, and cooling requirements which permit engine operation to Mach 9-10 without additional hydrogen for engine cooling. Studies have identified fabrication techniques and coolant passage configurations that increase fatigue life of the structure an order of magnitude over previous configurations.

Kelly, H. N.↗
NASA NTRS1976

Actively cooled airframe structures for high-speed flight

An assessment of forced convectively cooled aircraft structures is presented based on recent and on-going studies. Particular emphasis is given to contractual efforts in which large panels of three different concepts are being designed and fabricated for cyclic thermal-structural tests at the Langley Research Center. Results of ambient temperature fatigue tests of small specimens of these concepts are reviewed. Aspects of conceptual and detail designs, material selection, fabrication, reliability, and heat-load/hydrogen fuel heat-sink matching are discussed. Results to date indicate that active cooling significantly impacts the structural design process, and, despite the use of conventional aluminum materials, advanced complex fabrication processes are required.

Nowak, R. J.↗