By: Alina Rudani
As air travel serves as an essential form of transport, constant improvements are made to aircraft design to promote efficiency and sustainability. Morphing wings (also called shape-shifting or adaptive wings) are a relatively new airplane wing technology inspired by birds. This type of airfoil easily configures from one shape to another to accommodate different phases in flight (Min et al., 2010). Integrating morphing wings in aircraft design could be revolutionary for promoting aerodynamic efficiency and reducing fuel usage.
Aerodynamic Efficiency
A significant benefit of implementing morphing wings in aircraft design is that it increases lift (Ninian & Dakka, 2017); this promotes flight and decreases the work a plane needs to do in-flight (Ninian & Dakka, 2017). Studies performed by Ninian and Dakka, which consists of putting morphing wings through wind tunnel testing, show that the adaptive wing had a greater lift coefficient than conventional wing designs (Ninian & Dakka, 2017). Notably, this was observed in smaller angles of attacks, where lift is generally low for most airfoils (Ninian & Dakka, 2017).
Morphing wings can also produce less drag in flight. The design structure of morphing wings typically has transition regions and fewer disjoints in the wing, unlike most conventional designs (Ninian & Dakka, 2017). This arrangement ensures that air does not travel from areas of high pressure to low pressure, creating vortices which slow down the aircraft (Green, 1995). Consequently, the aircraft does not have to work as strenuously to overcome these drag forces, ultimately reducing fuel usage (Ninian & Dakka, 2017).
Although aerodynamically favorable, the wing design can cause issues for airfoil functionality. Morphing wings have very few discontinuities on their surface and instead have a large network of joints where stress accumulates. When the aircraft undergoes significant stress forces, the wing can permanently distort, encouraging vortex formation and even complete loss of function. The airfoil would therefore have to be replaced, which over time can be costly (Ameduri & Concilio, 2020).
Environmental Impacts
There has been an overall increase in fuel consumption by aircraft, with a global peak in 2019 of 95 billion gallons just from commercial airlines (Commercial Airlines: Worldwide Fuel Consumption 2005-2022 | Statista, n.d.). Additionally, according to the International Air Transport Association, the cost of jet fuel has increased by over 149% compared to last year ("What You Need to Know About Aviation Fuel Prices," 2022). The use of morphing wings in the aviation industry is predicted to be more fuel-preserving and cost-effective since it increases aerodynamic efficiency and reduces the effort required for the aircraft to reach adequate flying conditions (Ameduri & Concilio, 2020). Consequently, this will lower the amount of CO2 released via flying and help reduce the aviation industry's negative impact on global warming (Ninian & Dakka, 2017).
However, the morphing wings’ material design and structure may not be sustainable for long-term use (Ameduri & Concilio, 2020). Due to the large number of stress forces faced in flight, the airfoil’s outer material is subject to severe deformation, implying the need to periodically alter or replace parts of the wing (Ameduri & Concilio, 2020). However, research is currently being conducted for design improvement. For instance, researchers from the University of Toronto suggest adding piezoelectric crystals to the wings’ surface, which absorbs stress and permits the wing to continue functioning under harsh air circulation (Galantai, n.d.).
Although this may be effective, manufacturing the crystals is complex and costly. A cheaper alternative is ceramic piezoelectric crystals. However, they cannot absorb as much shock as pure piezo crystals (Raghunath & Science, n.d.).
Conclusion
In conclusion, morphing wings can significantly upgrade modern aircraft design with more materials testing. It has proved advantageous for increasing aerodynamic efficiency and reducing fuel usage. More research is needed, however, to improve the overall durability of the wings so they can be a practical addition to airplanes everywhere.
References
Commercial airlines: Worldwide fuel consumption 2005-2022 | Statista. (n.d.). Retrieved July 8, 2022, from https://www.statista.com/statistics/655057/fuel-consumption-of-airlines-worldwide/
Ameduri, S., & Concilio, A. (2020). Morphing wings review: Aims, challenges, and current open issues of a technology: Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science. https://doi.org/10.1177/0954406220944423
Galantai, V. P. (n.d.). Design and Analysis of Morphing Wing for Unmanned Aerial Vehicles. 87.
Green, S. I. (1995). Wing Tip Vortices. In S. I. Green (Ed.), Fluid Vortices (pp. 427–469). Springer Netherlands. https://doi.org/10.1007/978-94-011-0249-0_10
Min, Z., Kien, V. K., & Richard, L. J. Y. (2010). Aircraft morphing wing concepts with radical geometry change. The IES Journal Part A: Civil & Structural Engineering, 3(3), 188–195. https://doi.org/10.1080/19373261003607972
Ninian, D., & Dakka, S. M. (2017). Design, Development and Testing of Shape Shifting Wing Model. Aerospace, 4(4), 52. https://doi.org/10.3390/aerospace4040052
Raghunath, R., & Science, I. I. of. (n.d.). New ceramic material could cut down cost of piezoelectric devices. Retrieved July 8, 2022, from https://phys.org/news/2018-05-ceramic-material-piezoelectric-devices.html
What You Need to Know About Aviation Fuel Prices. (2022, May 4). FLYING Magazine. https://www.flyingmag.com/what-you-need-to-know-about-aviation-fuel-prices/
