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Anthony, F. M.

Publications and source records attributed to Anthony, F. M..

Design and fabrication of a stringer stiffened discrete-tube actively cooled panel for a hypersonic aircraft

A 0.61 x 1.22 m (2 x 4 ft) test panel was fabricated and delivered to the Langley Research Center for assessment of the thermal and structural features of the optimized panel design. The panel concept incorporated an aluminum alloy surface panel actively cooled by a network of discrete, parallel, redundant, counterflow passage interconnected with appropriate manifolding, and assembled by adhesive bonding. The cooled skin was stiffened with a mechanically fastened conventional substructure of stringers and frames. A 40 water/60 glycol solution was the coolant. Low pressure leak testing, radiography, holography and infrared scanning were applied at various stages of fabrication to assess integrity and uniformity. By nondestructively inspecting selected specimens which were subsequently tested to destruction, it was possible to refine inspection standards as applied to this cooled panel design.

Anthony, F. M.↗

Development and validation of cryogenic foam insulation for LH2 subsonic transports

Fourteen foam insulation specimens were tested. Some were plain foam while others contained flame retardants, chopped fiberglass reinforcement and/or vapor barriers. The thermal performance of the insulation was determined by measuring the rate at which LH2 boiled from an aluminum tank insulated with the test material. The test specimens were approximately 50 mm (2 in.) thick. They were structurally scaled so that the test cycle would duplicate the maximum thermal stresses predicted for the thicker insulation of an aircraft liquid hydrogen fuel tank during a typical subsonic flight. The simulated flight cycle of approximately 10 minutes duration heated the other insulation surface to 316 K (110 F) and cooled it to 226 K (20 F) while the inner insulation surface remained at liquid hydrogen temperature of 20 K (-423 F). Two urethane foam insulations exceeded the initial life goal of 2400 simulated flight cycles and sustained 4400 cycles with only minor damage. The addition of fiberglass reinforcement of flame retardant materials to an insulation degraded thermal performance and/or the life of the foam material. Installation of vapor barriers enhanced the structural integrity of the material but did not improve thermal performance. All of the foams tested were available materials; none were developed specifically for LH2 service.

Anthony, F. M.↗

Design and fabrication of a skin stringer discrete tube actively cooled structural panel

The design optimization and practical implementation of actively cooled structural panel concepts was investigated. The desired actively cooled structural panel consisted of the cooled skin and a substructure. The primary load carrying components were fabricated from 2024-T3 aliminum alloy. The 3003-H14 coolant passage tubing was chosen because of its excellent corrosion resistance, workability needed to obtain the desired cross sectional shape, and strength. The Epon 951 adhesive was selected for its excellent structural properties and is the thinnest of available films, 0.064 mm. The Eccobond 58C silver filled epoxy was chosen because of its high thermal conductivity, and the alumina filled Epon 828 was chosen for structural and expansion characteristics.

Anthony, F. M.↗

Internal convective cooling systems for hypersonic aircraft

Parametric studies were conducted to investigate the relative merits of construction materials, coolants, and cooled panel concepts for internal convective cooling systems applied to airframe structures of hydrogen-fueled hypersonic aircraft. These parametric studies were then used as a means of comparing various cooled structural arrangements for a hypersonic transport and a hypersonic research airplane. The cooled airplane studies emphasized weight aspects as related to the choice of materials, structural arrangements, structural temperatures, and matching of the cooling system heat load to the available hydrogen fuel-flow heat sink. Consideration was given to reliability and to fatigue and fracture aspects, as well. Even when auxiliary thermal protection system items such as heat shielding, insulation, and excess hydrogen for cooling are considered the more attractive actively cooled airframe concepts indicated potential payload increases of from 40 percent to over 100 percent for the hypersonic transport as compared to the results of previous studies of the same vehicle configuration with an uncooled airframe.

Anthony, F. M.↗

Data and results from a study of internal convective cooling systems for hypersonic aircraft

An extensive survey of current and future airframe construction materials and coolants was conducted, so that the most promising candidates could be examined for cooled-panel, cooling-system and airframe concepts. Consideration was given to over 100 structural materials, 50 coolants, 6 classes of structural panel concepts, 4 classes of thermal panel concepts with numerous variations, and 3 overall cooled airframe design approaches, including unshielded, shielded, and dual temperature types. The concept identification and parametric comparison phase examined all major elements of the convectively cooled airframe, including the differing requirements at various locations on the aircraft. The parametric results were used for the investigation to two separate vehicles, a hypersonic transport with a length of 96 meters (314 feet) and a weight of 24,000 kg (528,600 lb) and a hypersonic research airplane, with a length of 25m (80 ft) and a weight of 20,300 kg (447,000 lb).

Anthony, F. M.↗

Design of a convective cooling system for a Mach 6 hypersonic transport airframe.

The design of a convective cooling system for an aluminum alloy airframe was established to verify preliminary weight estimates and to define future development requirements. A water glycol coolant was circulated through a closed loop network of supply and return lines to absorb incident aerodynamic heating from structural skin panels with integral passages and to transfer this heat input to a heat exchanger where it is rejected to the hydrogen fuel. Partial shielding of the aluminum alloy structure reduced heat loads to levels compatible with engine fuel flow requirements.

Anthony, F. M.↗

Comparison of thermal protection systems for a space shuttle booster and orbiter.

Selection of the most appropriate thermal protection system design approaches requires evaluation of alternate concepts. Such an evaluation was conducted for a representative booster and orbiter configurations. TPS concept examined for the booster included heat sink, metallic reradiative, reusable surface insulation, and surface cooled types. For the orbiter, emphasis was placed on metallic reradiative and reusable surface insulation concepts with uncooled, phase change material cooled, and water-cooled substructures. Three insulation materials of different densities were examined for the orbiter reradiative TPS to identify the weight sensitivity of various substructural design approaches to this variable.

Anthony, F. M.↗

Design and evaluation of active cooling systems for Mach 6 cruise vehicle wings

Active cooling systems, which included transpiration, film, and convective cooling concepts, are examined. Coolants included hydrogen, helium, air, and water. Heat shields, radiation barriers, and thermal insulation are considered to reduce heat flow to the cooling systems. Wing sweep angles are varied from 0 deg to 75 deg and wing leading edge radii of 0.05 inch and 2.0 inches are examined. Structural temperatures are varied to allow comparison of aluminum alloy, titanium alloy, and superalloy structural materials. Cooled wing concepts are compared among themselves, and with the uncooled concept on the basis of structural weight, cooling system weight, and coolant weight.

Mcconarty, W. A.↗

Evaluation of active cooling systems for a Mach 6 hypersonic transport airframe, part 2

Transpiration and convective cooling concepts are examined for the fuselage and tail surface of a Mach 6 hypersonic transport aircraft. Hydrogen, helium, and water are considered as coolants. Heat shields and radiation barriers are examined to reduce heat flow to the cooled structures. The weight and insulation requirements for the cryogenic fuel tanks are examined so that realistic totals can be estimated for the complete fuselage and tail. Structural temperatures are varied to allow comparison of aluminum alloy, titanium alloy, and superalloy contruction materials. The results of the study are combined with results obtained on the wing structure, obtained in a previous study, to estimate weights for the complete airframe. The concepts are compared among themselves, and with the uncooled concept on the basis of structural weight, cooling system weight, and coolant weight.

Helenbrook, R. G.↗