Results 1 to 10 of about 3,903 (185)

Superelastic High-Entropy Oxide Ceramic Aerogels for Thermal Superinsulation and Sealing at Extreme Conditions. [PDF]

Adv Sci (Weinh)
A high‐entropy oxide ceramic of (Gd1/2Lu1/2)2(Ti1/3Zr1/3Hf1/3)2O7 is prepared through a molecular synthesis route of pyrolytic solid‐solution reactions. The architectured nanofiber aerogel manifests unprecedented thermomechanical properties, including superelastic compressibility of 98% from −196 to 1500 °C, and thermal superinsulation capacity (24.14 ...
Jiang X, Du T, Fan H, Liu J, Su Y, He P, Chen H, Hu L, Zhang Y, Zhang Q.   +9 more
europepmc   +2 more sources

Control-relevant modeling of hypersonic vehicles [PDF]

2009 American Control Conference, 2009
Scramjet powered hypersonic vehicles represent the next critical step toward achieving NASA's vision for Highly Reliable Reusable Launch Systems (HRRLS), affordable space access, planetary re-entry systems, and global reach vehicles. The design of such vehicles is a very interdisciplinary and highly complex problem.
Jerald M. Vogel, Atul G. Kelkar, George Inger, Christopher E. Whitmer, Alan Sidlinger, Armando A. Rodriguez   +5 more
openaire   +1 more source

Aeroelasticity of a Generic Hypersonic Vehicle [PDF]

43rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, 2002
Peer Reviewed ; http://deepblue.lib.umich.edu/bitstream/2027.42/76282/1/AIAA-2002-1209-307 ...
Thuruthimattam, Biju J., Friedmann, Peretz P., Powell, Kenneth G., Mcnamara, Jack   +3 more
openaire   +1 more source

Predictor–Corrector Guidance for a Hypersonic Morphing Vehicle

Aerospace, 2023
In an effort to address the problem of hypersonic morphing vehicles reaching the target while avoiding no-fly zones, an improved predictor–corrector guidance method is proposed. Firstly, the aircraft motion model and the constraint model are established. Then, the basic algorithm is given.
Dongdong Yao, Qunli Xia
openaire   +2 more sources

Transpiration cooling of a hypersonic vehicle

, 2021
In this thesis, a porous Ultra-High-Temperature-Ceramic (UHTC) made of zirconium diboride (ZrB2) is qualified for the purpose for transpiration cooling for the first time. Subsequently, the mixing mechanism between the coolant and a laminar, hypersonic boundary-layer gas at the wall downstream of a transpiration-cooled injector is investigated.
openaire   +2 more sources

Materials and structures for hypersonic vehicles [PDF]

Journal of Aircraft, 1989
Hypersonic vehicles are envisioned to require, in addition to carbon-carbon and ceramic-matrix composities for leading edges heated to above 2000 F, such 600 to 1800 F operating temperature materials as advanced Ti alloys, nickel aluminides, and metal-matrix composited; These possess the necessary low density and high strength and stiffness.
Darrel R. Tenney, W. Barry Lisagor, Sidney C. Dixon   +2 more
openaire   +1 more source

Impact of Cattaneo–Christov Heat and Mass Flux on MHD Hybrid Nanofluid Flow Over an Extending Surface With Convective and Mass Flux Effects

Asia-Pacific Journal of Chemical Engineering, EarlyView.
ABSTRACT This study investigates the flow of a magnetized hybrid nanofluid over a permeable stretching surface. The mass and thermal transport within the system is regulated using the Cattaneo–Christov flux theory. The fluid is additionally subjected to thermophoresis, chemical reaction, Brownian motion, and activation energy effects.
Ebrahem A. Algehyne, Abdul Bariq, Mounirah Areshi, Fahad Maqbul Alamrani, Zehba Raizah, Izharul Haq, Anwar Saeed   +6 more
wiley   +1 more source

Sliding Mode Control in Aerospace Applications: A Survey

International Journal of Robust and Nonlinear Control, EarlyView.
ABSTRACT Sliding mode control (SMC) enjoys robustness to matched and unmatched (in the case of minimum phase input‐output dynamics) bounded perturbations, and finite time convergence. Second‐order and higher‐order sliding mode control systems (2‐SMC/HOSMC) retain all the advantages of sliding mode control, but in addition can be applied to systems of ...
Yuri Shtessel, Christopher Edwards
wiley   +1 more source

X-43 Hypersonic Vehicle Technology Development [PDF]

56th International Astronautical Congress of the International Astronautical Federation, the International Academy of Astronautics, and the International Institute of Space Law, 2005
Abstract NASA recently completed two major programs in hypersonics: Hyper-X, with the record-breaking flights of the X-43A, and the next generation launch technology (NGLT) program. The X-43A flights, the culmination of the Hyper-X program, were the first-ever examples of a scramjet engine propelling a hypersonic vehicle and provided unique ...
Randall T. Voland, Lawrence D. Huebner, Charles R. McClinton   +2 more
openaire   +1 more source

The Unintended Consequences of German Deterrence

Global Policy, EarlyView.
ABSTRACT Germany's evolving deterrence posture boils down to continued participation in NATO nuclear sharing and an ambitious conventional rearmament program. Due to its non‐nuclear status and a result of decades of underinvestment, Germany prioritizes modern conventional weapons.
Ulrich Kühn
wiley   +1 more source