Results 51 to 60 of about 23,423 (133)

Spring and Power in Hovering Ornithopters

Advanced Intelligent Systems, Volume 7, Issue 7, July 2025.
Only small ornithopters can hover, longest at the hummingbird size. This article reviews the drive and power of these hovering machines, focusing on elastic energy and thrust boosters. Unlike two‐winged designs, X‐winged and multiple‐V‐winged ornithopters benefit from lower disk loading and slower, smaller wingbeats, and the clap‐and‐fling effect ...
Gih‐Keong Lau, Yao‐Wei Chin, Shih‐Chun Lin, Yu‐Hsiang Lai, Boo Cheong Khoo   +4 more
wiley   +1 more source

Design Optimization of a Pseudo-Rigid-Compliant Mechanism for Large, Continuous, and Smooth Morphing of Airfoil Camber

Aerospace
This work introduces a novel variable camber mechanism that combines the high-load capacity, structural stability, and mechanical efficiency of rigid-body mechanisms with the adaptability, lightweight design, and continuous and smooth motion of compliant
Victor Alulema, Victor Hidalgo, Edgar Cando, Esteban Valencia   +3 more
doaj   +1 more source

Compliant Mechanism Synthesis Using Nonlinear Elastic Topology Optimization With Variable Boundary Conditions

International Journal for Numerical Methods in Engineering, Volume 126, Issue 1, 15 January 2025.
ABSTRACT In topology optimization of compliant mechanisms, the specific placement of boundary conditions strongly affects the resulting material distribution and performance of the design. At the same time, the most effective locations of the loads and supports are often difficult to find manually.
Lee R. Alacoque, Anurag Bhattacharyya, Kai A. James   +2 more
wiley   +1 more source

Continuous morphing camber for aerodynamic surfaces

, 2023
reservedSin dagli albori, l’uomo ha cercato di imitare ed ispirarsi alla natura in ogni ambito artistico e tecnico. Ne è un esempio il fascino e l’interesse che il genere umano ha riservato e riserva riguardo il volo degli uccelli, i quali sono in grado
MICOLI, FRANCESCO
core  

Comparative Analysis Among Different Performance Improvement Techniques for Wind Turbines in Terms of Energy and Economy for Small, Medium, and Large‐Scale Applications

International Journal of Energy Research, Volume 2025, Issue 1, 2025.
With a view to finding the best approach to maximize the wind energy harvesting from wind turbines, this research has focused towards assessing the effects of different innovative modifications to wind turbines at different wind speed conditions and comparing them in terms of aerodynamic performance, economy, and environmental impact.
Mim Mashrur Ahmed, Mahadi Hasan Masud, Md. Hasibul Hasan Himel, Mhia Md. Zaglul Shahadat, Mucahit Aydin   +4 more
wiley   +1 more source

Experimental and Numerical Analysis of the Aerodynamic Characteristics of the Flexing Wing With Active Camber Design

International Journal of Aerospace Engineering, Volume 2025, Issue 1, 2025.
The flexing/morphing concept is a means of improving wings’ aerodynamic performance. Morphing technology such as the fishbone active camber (FishBAC) design has demonstrated drag reduction of over 30% at moderate angles of attack (AoAs) and 40% at higher AoAs and tail deflections compared to plain flap systems.
Bassam Rakhshani, Nathalie Samson, Tony Leslie, Kan Xie   +3 more
wiley   +1 more source

Enhancing Unmanned Aerial Vehicle Performance: A Comprehensive Review of Aerodynamic Improvement Techniques at Low Reynolds Numbers

International Journal of Aerospace Engineering, Volume 2025, Issue 1, 2025.
The increasingly prominent function of unmanned aerial vehicles (UAVs) across fields ranging from logistics and surveillance to farming and research calls for ongoing innovation in their flight efficiency. This study probes the effect of making strategic alterations in the designs of UAVs’ wings, including the implementation of dogtooth shapes, on such
Mohammad Hossein Moghimi Esfandabadi, Sohrab Panahandeh Taghi-Abad, Mohammad Hassan DJavarshakian, Adel Ghenaiet   +3 more
wiley   +1 more source

Design and Aerodynamic Performance Study of a Butterfly‐Inspired Vertical Axis Wind Turbine for Urban and Aviation Zone Wind Energy Applications

Modelling and Simulation in Engineering, Volume 2025, Issue 1, 2025.
This study presents the development of a butterfly‐inspired vertical axis wind turbine (BAWT), integrating drag‐ and lift‐based mechanisms inspired by biological structures. By combining Savonius rotors, known for their self‐starting capability and torque stability at low wind speeds, with airfoil blades that enhance performance at higher tip‐speed ...
Avaesprabha Charlesantonyraj, Sundhar Baskar, Senthil Kumar Madasamy, Laxana Sourirajan, Naveen Kumar Kulandaiyappan, Beena Stanislaus Arputharaj, Subhav Singh, Khristina Maksudovna Vafaeva, Parvathy Rajendran, Vijayanandh Raja, Houari Ameur   +10 more
wiley   +1 more source

The effect of twist morphing on aerodynamic performance of finite wing at low Reynolds number [PDF]

EPJ Web of Conferences
This study experimentally investigates the effect of twist morphing on the aerodynamic characteristics of a finite wing at low Reynolds numbers (Re). As the base model, a NACA 0018 airfoil with an aspect ratio of 4 is used.
Gunes Yasemin B., Eroğlu Ali Emirhan, Durhasan Tahir, Karasu İlyas, Pinar Engin   +4 more
doaj   +1 more source

Evolutionary history of an island endemic, the Azorean common quail

Molecular Ecology, Volume 33, Issue 24, December 2024.
Abstract Oceanic islands are characterized by conditions that favour diversification into endemic lineages that can be very different from their mainland counterparts. This can be the result of fast phenotypic divergence due to drift or the result of slower adaptation to local conditions. This uniqueness can obscure their evolutionary history.
Sara Ravagni, Ines Sanchez‐Donoso, Irene Jiménez‐Blasco, Pedro Andrade, Manel Puigcerver, Ana Chorão Guedes, Raquel Godinho, David Gonçalves, Manuel Leitão, Jennifer A. Leonard, José Domingo Rodríguez‐Teijeiro, Carles Vilà   +11 more
wiley   +1 more source