Advances in Aerospace Sciences and Technology III

A special issue of Aerospace (ISSN 2226-4310).

Deadline for manuscript submissions: closed (31 December 2022) | Viewed by 34870

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School of Engineering, University of Glasgow, James Watt Building South, University Avenue, Glasgow G12 8QQ, Scotland, UK
Interests: aerodynamic technologies; flow and flight control systems; shock physics; aerospace design and optimization; flow diagnostics
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Dear Colleagues,

This Special Issue collects feature papers (original research articles or comprehensive review papers) in aerospace research fields. Highly experienced practitioners from various fields within the journal’s scope (https://www.mdpi.com/journal/aerospace/about) are welcome to contribute papers, highlighting the latest developments in their research area or a detailed summary of their own work done thus far. All papers to be published in this collection will be solicited and selected by the guest editor; a very high standard will be set in the selection of prospective authors and submitted papers, and those papers will be published, free of charge, in open access after peer review on condition that no valid rejection report is received during the peer-review process.

The submission deadline for this round of call for papers is 31 December 2022.

Prof. Dr. Konstantinos Kontis
Guest Editor

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Published Papers (14 papers)

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Research

13 pages, 832 KiB  
Article
Implementation of a Holistic MCDM-Based Approach to Assess and Compare Aircraft, under the Prism of Sustainable Aviation
by Dionysios N. Markatos and Spiros G. Pantelakis
Aerospace 2023, 10(3), 240; https://doi.org/10.3390/aerospace10030240 - 01 Mar 2023
Cited by 4 | Viewed by 1338
Abstract
Sustainability represents a key issue for the future of the aviation industry. The current work aims to assess and compare aircraft, under the prism of sustainable aviation. In the proposed approach, sustainability is understood as a trade-off between technological sustainability, economic competitiveness/costs, and [...] Read more.
Sustainability represents a key issue for the future of the aviation industry. The current work aims to assess and compare aircraft, under the prism of sustainable aviation. In the proposed approach, sustainability is understood as a trade-off between technological sustainability, economic competitiveness/costs, and ecological sustainability, with the latter also including circular economy aspects. To handle the trade-offs and lead to an effective decision, a multi-criteria decision-making (MCDM) methodology is applied, combining the analytic hierarchy process (AHP) and an appropriate weighted addition model. To demonstrate the proposed approach, a set of commercial aircraft incorporating novel fuel/propulsion technologies are compared and ranked with regards to their sustainability, using the metric of sustainability introduced. The dependency of the obtained ranking on the significance attributed to each of the sustainability aspects considered was also performed and discussed. To verify the reliability of the proposed approach, the obtained results are also compared with those obtained from a popular ranking tool from the literature. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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31 pages, 13809 KiB  
Article
Numerical Analysis of Glauert Inflow Formula for Single-Rotor Helicopter in Steady-Level Flight below Stall-Flutter Limit
by Marjan Dodic, Branimir Krstic, Bosko Rasuo, Mirko Dinulovic and Aleksandar Bengin
Aerospace 2023, 10(3), 238; https://doi.org/10.3390/aerospace10030238 - 28 Feb 2023
Cited by 3 | Viewed by 1934
Abstract
This article addresses the numerical computation problem of induced inflow ratio based on the helicopter momentum theory in forward flight. The Glauert inflow formula (equation) is a nonlinear equation usually solved by the Newton–Raphson method in a relatively small number of iterations. However, [...] Read more.
This article addresses the numerical computation problem of induced inflow ratio based on the helicopter momentum theory in forward flight. The Glauert inflow formula (equation) is a nonlinear equation usually solved by the Newton–Raphson method in a relatively small number of iterations. However, many high-order convergence multipoint iterative methods have been developed over the last decade. The study examines several selected methods in terms of finding ones that provide a solution in only one iteration with acceptable accuracy. Furthermore, the influence of initial guesses on the accuracy of the obtained solutions has been investigated. In this regard, the practical range of parameters of the Glauert inflow equation for helicopters in forward flight is roughly determined by simplified modeling of a power and stall-flutter limitation. For these purposes, a basic low-fidelity longitudinal trim model of a single-rotor helicopter in steady-level flight is modified and numerically solved by a symbolic transformation of a system of 20+ nonlinear equations into a single nonlinear equation. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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16 pages, 12259 KiB  
Article
Attitude Dynamics of Spinning Magnetic LEO/VLEO Satellites
by Vladimir S. Aslanov and Dmitry A. Sizov
Aerospace 2023, 10(2), 192; https://doi.org/10.3390/aerospace10020192 - 17 Feb 2023
Cited by 2 | Viewed by 1495
Abstract
With the growing popularity of small satellites, the interaction with the air in low and especially in very low Earth orbits becomes a significant resource for passive angular stabilisation. However, the possibility of spin motion remains a considerable challenge for missions involving aerodynamically [...] Read more.
With the growing popularity of small satellites, the interaction with the air in low and especially in very low Earth orbits becomes a significant resource for passive angular stabilisation. However, the possibility of spin motion remains a considerable challenge for missions involving aerodynamically stabilised satellites. The goal of this paper was to investigate the attitude motion of arbitrarily spinning satellites in LEO and VLEO under the action of aerodynamic, gravitational, and magnetic torques, taking into account the aerodynamic damping. Using an umbrella-shaped deployable satellite as an example, the study demonstrated that both regular and chaotic attitude regimes are possible in the attitude motion. The occurrence of chaos was verified by means of Poincaré sections. The results revealed that, to prevent chaotic motion, active attitude control and reliable deployment techniques for aerodynamically stabilised satellites are needed. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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22 pages, 8429 KiB  
Article
Influence of Spinner Shape on Droplet Impact over Rotating Spinners
by Xuan Gao, Borong Qiu, Zongjie Wang and Haiwang Li
Aerospace 2023, 10(1), 68; https://doi.org/10.3390/aerospace10010068 - 09 Jan 2023
Cited by 2 | Viewed by 1678
Abstract
Droplet impact affects water collection, which is the key to investigating the icing process on an aero-engine spinner. Different from a stationary spinner, droplet impact is affected by Coriolis acceleration and centrifugal acceleration on rotating aero-engine spinners, showing different impact dynamics. Based on [...] Read more.
Droplet impact affects water collection, which is the key to investigating the icing process on an aero-engine spinner. Different from a stationary spinner, droplet impact is affected by Coriolis acceleration and centrifugal acceleration on rotating aero-engine spinners, showing different impact dynamics. Based on the Eulerian method, using the rotating coordinate system we numerically investigated droplet impact characteristics on three different shapes of aero-engine spinners using ANSYS Fluent. The results indicate that the impact area covered all the windward surface on the conical spinner, and only covered the windward surface prior to the impingement limit of the elliptical spinner and the coniptical spinner. The sensitivity of water collection to inflow velocity declined in the order of coniptical the spinner, the elliptical spinner, and the conical spinner. In addition, the elliptical region could effectively improve aerodynamic performance, as shown in a lower total pressure loss through the spinner. This work is relevant to the anti-icing system of a rotating aero-engine spinner. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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23 pages, 15719 KiB  
Article
Aluminum Particle Ignition Studies with Focus on Effect of Oxide Barrier
by Nadir Yilmaz, Burl Donaldson and Walt Gill
Aerospace 2023, 10(1), 45; https://doi.org/10.3390/aerospace10010045 - 03 Jan 2023
Cited by 5 | Viewed by 1524
Abstract
Aluminum particle ignition behavior in open atmosphere rocket propellants fires is of particular interest for preventing accidents for rockets carrying high-value payloads. For nominal motor pressures, aluminum particles oxidize to aluminum oxide in the gas phase and release significant combustion energy while minimizing [...] Read more.
Aluminum particle ignition behavior in open atmosphere rocket propellants fires is of particular interest for preventing accidents for rockets carrying high-value payloads. For nominal motor pressures, aluminum particles oxidize to aluminum oxide in the gas phase and release significant combustion energy while minimizing motor instability. During rocket abort or launch pad malfunction which occur under atmospheric or low pressure, behavior of aluminum particle combustion becomes complex and aluminum appears to melt, agglomerate or form a skeletal structure. Furthermore, an oxide shell of alumina instantly forms on any fresh aluminum surface which is exposed to an oxidizing environment. Aluminum combustion then strongly depends on the oxide layer growth, which is influenced by causative factors, including particle size, environmental gas composition, and heating rate. This work focuses on the effect of the oxide barrier which forms on the surface of aluminum that is recognized to impede combustion of aluminum in solid rocket propellants. Understanding the mechanism for breach of this barrier is deemed to be an important consideration in the overall process. In this discussion, results of various experiments will be discussed which have a bearing on this process. Basically, a recognized criterion is the melting of the oxide layer at 2350 K is sufficient. However, in other situations, depending on the mechanism of oxide formation, there will occur defects in the oxide shell which provide for aluminum ignition at lower temperatures. For slow heating in an oxidizing environment, where the oxide layer can grow thick, then ignition is more difficult. Because there is no uniform model to establish an ignition criterion due to the unknown history of an aluminum particle, this paper reports experimental findings involving oxyacetylene torch, thermogravimetric analysis with differential scanning calorimeter, aluminum particle heating, electric ignition and aluminum powder heating, to address the influence of the oxide layer on the aluminum particle ignition. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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23 pages, 16997 KiB  
Article
Trajectory Optimization with Complex Obstacle Avoidance Constraints via Homotopy Network Sequential Convex Programming
by Wenbo Li, Wentao Li, Lin Cheng and Shengping Gong
Aerospace 2022, 9(11), 720; https://doi.org/10.3390/aerospace9110720 - 16 Nov 2022
Cited by 4 | Viewed by 1905
Abstract
Space vehicles’ real-time trajectory optimization is the key to future automatic guidance. Still, the current sequential convex programming (SCP) method suffers from a low convergence rate and poor real-time performance when dealing with complex obstacle avoidance constraints (OACs). Given the above challenges, this [...] Read more.
Space vehicles’ real-time trajectory optimization is the key to future automatic guidance. Still, the current sequential convex programming (SCP) method suffers from a low convergence rate and poor real-time performance when dealing with complex obstacle avoidance constraints (OACs). Given the above challenges, this work combines homotopy and neural network techniques with SCP to propose an innovative algorithm. Firstly, a neural network was used to fit the minimum signed distance field at obstacles’ different “growth” states to represent the OACs. Then, the network was embedded with the SCP framework, thus smoothly transforming the OACs from simple to complex. Numerical simulations showed that the proposed algorithm can efficiently deal with trajectory optimization under complex OACs such as a “maze”, and the algorithm has a high convergence rate and flexible extensibility. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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25 pages, 7146 KiB  
Article
A New Mapped WENO Method for Hyperbolic Problems
by U S Vevek, Bin Zang and T. H. New
Aerospace 2022, 9(10), 623; https://doi.org/10.3390/aerospace9100623 - 19 Oct 2022
Viewed by 1463
Abstract
In this study, a new family of rational mapping functions gRM(ω;k,m,s) is introduced for seventh-order WENO schemes. gRM is a more general family of mapping functions, which includes other mapping functions such [...] Read more.
In this study, a new family of rational mapping functions gRM(ω;k,m,s) is introduced for seventh-order WENO schemes. gRM is a more general family of mapping functions, which includes other mapping functions such as gM and gIM as special cases. The mapped WENO scheme WENO-IM(2,0.1), which uses gIM, performs excellently at fifth order but rather poorly at seventh order. The reason for this loss of accuracy was found to be the over-amplification of very small weights by the mapping process, which can be traced back to the large slope of gIM at ω = 0. For m > 1, gRM can be designed to have a unit slope at ω = 0, which will preserve small weights with little to no amplification. It has been demonstrated through several one-dimensional linear advection test cases that the mapped WENO scheme WENO-RM(6,3,2 × 103), which uses the mapping function gRM(ω;6,3,2 × 103), outperforms both WENO-M and WENO-IM(2,0.1) at seventh order. The proposed scheme also performs better at a number of one-dimensional inviscid gas flow problems compared to other popular WENO schemes such as the WENO-Z scheme. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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23 pages, 11606 KiB  
Article
Framework for Estimating Performance and Associated Uncertainty for Modified Aircraft Configurations
by Casey L. Denham, Mayuresh Patil, Christopher J. Roy and Natalia Alexandrov
Aerospace 2022, 9(9), 490; https://doi.org/10.3390/aerospace9090490 - 01 Sep 2022
Cited by 2 | Viewed by 1602
Abstract
Flight testing has been the historical standard for determining aircraft airworthiness. However, increases in the cost of flight testing and the accuracy of inexpensive CFD encourage the adoption of certification by analysis to reduce or replace flight testing. A framework is introduced to [...] Read more.
Flight testing has been the historical standard for determining aircraft airworthiness. However, increases in the cost of flight testing and the accuracy of inexpensive CFD encourage the adoption of certification by analysis to reduce or replace flight testing. A framework is introduced to predict the performance in the special case of a modification to an existing, previously certified aircraft. This framework uses a combination of existing flight tests or high fidelity data of the original aircraft as well as lower fidelity data from CFD or wind tunnel testing of the original and modified configurations to create 6-DOF flight dynamics models. Two methods are presented which generate an updated flight dynamics model and estimate the model form uncertainty for the modified aircraft configuration using knowledge of the original aircraft. This updated dynamics model and uncertainty estimate are then used to conduct non-deterministic simulations with wind turbulence included. The framework is applied to an example aircraft system to demonstrate the ability to predict the performance and associated model from the uncertainty of modified aircraft configurations. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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15 pages, 1939 KiB  
Article
Experimental Study into Optimal Configuration and Operation of Two-Four Rotor Coaxial Systems for eVTOL Vehicles
by Jubilee Prasad Rao, Jonathan E. Holzsager, Marco M. Maia and Javier F. Diez
Aerospace 2022, 9(8), 452; https://doi.org/10.3390/aerospace9080452 - 17 Aug 2022
Cited by 3 | Viewed by 2270
Abstract
Coaxial rotors are utilized in multirotor aerial vehicles for the added thrust compared to independent rotors while keeping similar area footprints; however, performance losses should be considered. This experimental study analyzes the effects of varying motor duty cycle and propeller pitch values in [...] Read more.
Coaxial rotors are utilized in multirotor aerial vehicles for the added thrust compared to independent rotors while keeping similar area footprints; however, performance losses should be considered. This experimental study analyzes the effects of varying motor duty cycle and propeller pitch values in motor-propeller systems with two to four coaxial rotors. The results demonstrate that in a two-rotor coaxial system, to lessen the adverse effects of a front rotor’s backwash and operate at the maximum performance, only the back motor should be operated initially up to 75% duty cycle before using the front motor up to its 75% duty cycle. Additional thrust requirements should be generated from the back rotor and then from the front rotor up to their maximum duty cycles. In two, three, and four-rotor coaxial setups, total thrust output generated is 1.6, 2.1, and 2.5 times the thrust output at system thrust performance of 86%, 76%, and 66%, respectively, of that of an isolated rotor. In a four-rotor coaxial setup, the maximum system performance is achieved when the propeller pitch values gradually increase from the first to the last rotor. The gradual increments in propeller pitch values also result in more uniform thrust sharing among rotors. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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22 pages, 8175 KiB  
Article
Numerical Analysis on the Aerodynamic Characteristics of an X-wing Flapping Vehicle with Various Tails
by Huadong Li, Daochun Li, Tong Shen, Dawei Bie and Zi Kan
Aerospace 2022, 9(8), 440; https://doi.org/10.3390/aerospace9080440 - 11 Aug 2022
Cited by 6 | Viewed by 2180
Abstract
X-shaped flapping wings have excellent maneuverability and flight capabilities under low-Reynolds-number conditions. An appropriate tail can extend the range of a vehicle and improve its stability. This study takes two typical configurations, the inverted T-tail and the inverted V-tail, as the research object. [...] Read more.
X-shaped flapping wings have excellent maneuverability and flight capabilities under low-Reynolds-number conditions. An appropriate tail can extend the range of a vehicle and improve its stability. This study takes two typical configurations, the inverted T-tail and the inverted V-tail, as the research object. Considering the wings’ flexible deformation in the flapping process, the computational fluid dynamics method was used to calculate the vehicles’ aerodynamic characteristics, taking into account the aerodynamic interaction effect of the wings and tail. The results show that the wake of flapping wings can significantly reduce the forward flight performance of the tails. The maximum L/D ratio of the two tails decreased by about 38%, and the static stability was also dramatically reduced in the forward flight. The inverted V-tail has better performance in fast forward flight, while the inverted T-tail had better control characteristics at low speeds. The relationship between the tail layouts and aerodynamic performance is also discussed. When the inverted V-tail is in the optimal position, the longitudinal control moment can be doubled in the hovering state. This research provides a reference for the design and arrangement of flapping wings with tails, which is beneficial to the performance improvement of vehicles. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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18 pages, 31189 KiB  
Article
Design and Analysis of MataMorph-3: A Fully Morphing UAV with Camber-Morphing Wings and Tail Stabilizers
by Peter L. Bishay, James S. Kok, Luis J. Ferrusquilla, Brian M. Espinoza, Andrew Heness, Antonio Buendia, Sevada Zadoorian, Paul Lacson, Jonathan D. Ortiz, Ruiki Basilio and Daniel Olvera
Aerospace 2022, 9(7), 382; https://doi.org/10.3390/aerospace9070382 - 14 Jul 2022
Cited by 10 | Viewed by 4077
Abstract
Conventional aircraft use discrete flight control surfaces to maneuver during flight. The gaps and discontinuities of these control surfaces generate drag, which degrades aerodynamic and power efficiencies. Morphing technology aims to replace conventional wings with advanced wings that can change their shape to [...] Read more.
Conventional aircraft use discrete flight control surfaces to maneuver during flight. The gaps and discontinuities of these control surfaces generate drag, which degrades aerodynamic and power efficiencies. Morphing technology aims to replace conventional wings with advanced wings that can change their shape to control the aircraft with the minimum possible induced drag. This paper presents MataMorph-3, a fully morphing unmanned aerial vehicle (UAV) with camber-morphing wings and tail stabilizers. Although previous research has presented successful designs for camber-morphing wing core mechanisms, skin designs suffered from wrinkling, warping, or sagging problems that result in reduced reliability and aerodynamic efficiency. The wing and tail stabilizers of MataMorph-3 feature hybrid ribs with solid leading-edge sections that house servomotors, and compliant trailing-edge sections with integrated flexible ribbons that are connected to the servomotors to camber-morph the ribs. Thin laminated carbon fiber composite skin slides smoothly over the compliant rib sections upon morphing, guided by innovative trailing-edge sliders and skin-supporting linkage mechanisms strategically located between the ribs. Sample prototypes were built and tested to show the effectiveness of the proposed design solutions in enabling smooth camber-morphing. The proposed design provides a better alternative to stretchable skins in morphing airplane designs through the concept of skin sliding. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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17 pages, 7711 KiB  
Article
Conceptual Research on a Mono-Biplane Aerodynamics-Driven Morphing Aircraft
by Tingyu Guo, Liangtao Feng, Chenhua Zhu, Xiaopeng Zhou and Haixin Chen
Aerospace 2022, 9(7), 380; https://doi.org/10.3390/aerospace9070380 - 14 Jul 2022
Cited by 5 | Viewed by 2682
Abstract
The operation of aircrafts with high aspect ratio wings is usually vulnerable to low-standard airports and bad weather. A new concept for a mono-biplane aerodynamics-driven morphing aircraft is proposed. The movable and fixed wings form a biplane mode during takeoff and landing, while [...] Read more.
The operation of aircrafts with high aspect ratio wings is usually vulnerable to low-standard airports and bad weather. A new concept for a mono-biplane aerodynamics-driven morphing aircraft is proposed. The movable and fixed wings form a biplane mode during takeoff and landing, while they form a high aspect ratio monoplane mode when cruising. This novel form of morphing can obtain a high cruise L/D while reducing nearly 50% of the takeoff and landing wingspan. However, the wing area is kept unchanged while morphing. The aerodynamic force on the movable wing is controlled by the deflection of the flaps to drive the morphing. No additional driving actuator is needed. In this way, although the morphing scale is large, the penalty on the complexity, structural strength, weight, and internal space of the wing is low. Taking the RQ-4A “Global Hawk” as the design baseline, morphing of the mono-biplane could further extend the cruise wingspan and aspect ratio for a better range without increasing the takeoff and landing span. When the wingspan was restricted, it was shown that this morphing scheme could reach a range extension of more than 50% when compared with an aircraft with the same wing load and different layouts. The feasibility of this mono-biplane aerodynamics-driven morphing concept was initially verified through ground vehicle tests. The possible influence of the morphing process on aircraft stability and control is also discussed. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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21 pages, 11364 KiB  
Article
Vibro-Acoustic Modelling of Aeronautical Panels Reinforced by Unconventional Stiffeners
by Giovanni Fasulo, Pasquale Vitiello, Luigi Federico and Roberto Citarella
Aerospace 2022, 9(6), 327; https://doi.org/10.3390/aerospace9060327 - 17 Jun 2022
Cited by 3 | Viewed by 2489
Abstract
The purpose of this work is to characterise the vibro-acoustic behaviour of rectangular flat panels reinforced by “unconventional” stiffeners. Such panels are being increasingly employed in the aircraft industry in the case of composite fuselage, so that the assessment of the most efficient [...] Read more.
The purpose of this work is to characterise the vibro-acoustic behaviour of rectangular flat panels reinforced by “unconventional” stiffeners. Such panels are being increasingly employed in the aircraft industry in the case of composite fuselage, so that the assessment of the most efficient and accurate numerical techniques and modelling procedures to correctly predict their dynamic and acoustic behaviour is required. To this end, an analytical method, available from literature, has been initially employed to investigate on the main attributes of sound transmission loss properties of stiffened panels driven by an acoustic diffuse field excitation. Based on existing commercial codes, different numerical techniques have been implemented and deeply examined to assess their potentiality and restrictions. Among them, the Hybrid method has been eventually identified as the best compromise in terms of accuracy and computational effort. The drawbacks of deterministic and even Hybrid numerical approaches for medium–high frequency vibro-acoustic analysis when dealing with large structures, make use of the pure SEA approach compulsory. In particular, a refined tuning of a specific feature made available within the employed SEA analysis environment when dealing with reinforced shells is implemented as a potential solution to overcome the complexity in correctly modelling the examined unconventionally stiffened panels. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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17 pages, 10963 KiB  
Article
High-Performance Properties of an Aerospace Epoxy Resin Loaded with Carbon Nanofibers and Glycidyl Polyhedral Oligomeric Silsesquioxane
by Liberata Guadagno, Spiros Pantelakis, Andreas Strohmayer and Marialuigia Raimondo
Aerospace 2022, 9(4), 222; https://doi.org/10.3390/aerospace9040222 - 16 Apr 2022
Cited by 8 | Viewed by 2533
Abstract
This paper proposes a new multifunctional flame retardant carbon nanofiber/glycidyl polyhedral oligomeric silsesquioxane (GPOSS) epoxy formulation specially designed for lightweight composite materials capable of fulfilling the ever-changing demands of the future aerospace industry. The multifunctional resin was designed to satisfy structural and functional [...] Read more.
This paper proposes a new multifunctional flame retardant carbon nanofiber/glycidyl polyhedral oligomeric silsesquioxane (GPOSS) epoxy formulation specially designed for lightweight composite materials capable of fulfilling the ever-changing demands of the future aerospace industry. The multifunctional resin was designed to satisfy structural and functional requirements. In particular, this paper explores the advantages deriving from the combined use of GPOSS and CNFs (short carbon nanofibers) to obtain multifunctional resins. The multifunctional material was prepared by incorporating in the epoxy matrix heat-treated carbon nanofibers (CNFs) at the percentage of 0.5 wt% and GPOSS compound at 5 wt% in order to increase the mechanical performance, electrical conductivity, thermal stability and flame resistance property of the resulting nanocomposite. Dynamic mechanical analysis (DMA) shows that the values of the Storage Modulus (S.M.) of the resin alone and the resin containing solubilized GPOSS nanocages are almost similar in a wide range of temperatures (from 30 °C to 165 °C). The presence of CNFs, in the percentage of 0.5 wt%, determines an enhancement in the S.M. of 700 MPa from −30 °C to 180 °C with respect to the resin matrix and the resin/GPOSS systems. Hence, a value higher than 2700 MPa is detected from 30 °C to 110 °C. Furthermore, the electrical conductivity of the sample containing both GPOSS and CNFs reaches the value of 1.35 × 10−1 S/m, which is a very satisfying value to contrast the electrical insulating property of the epoxy systems. For the first time, TUNA tests have been performed on the formulation where the advantages of GPOSS and CNFs are combined. TUNA investigation highlights an electrically conductive network well distributed in the sample. The ignition time of the multifunctional nanocomposite is higher than that of the sample containing GPOSS alone of about 35%. Full article
(This article belongs to the Special Issue Advances in Aerospace Sciences and Technology III)
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