Aerospace Science and Technology最新文献

{"title":"Enhancement of flying wing aerodynamics in crossflow at high angle of attack using dual synthetic jets","authors":"Hao Wang,&nbsp;Zhenbing Luo,&nbsp;Xiong Deng,&nbsp;Yan Zhou,&nbsp;Jianyu Gong","doi":"10.1016/j.ast.2024.109773","DOIUrl":"10.1016/j.ast.2024.109773","url":null,"abstract":"<div><div>To address the asymmetric flow field of the flying wing under cross-flow conditions at high angles of attack, dual synthetic jet actuators (DSJAs) are positioned at the leading edge of the windward side. DSJ control effectively affects the flow separation structure on the windward side, thereby enhancing leading-edge suction. This leads to both lift enhancement and drag reduction. Furthermore, it strengthens the stabilizing roll moment and improves lateral static stability. Additionally, the effective suppression of the separation zone significantly reduces the aerodynamic load fluctuations of the flying wing after control. In terms of excitation frequency, low-frequency excitation more effectively generates lift, transfers energy downstream, promotes momentum transfer, and results in an 8.2% increase in lift. Moreover, the DSJ excitation exhibits fast response characteristics, with the entire flow establishment process taking only 190 ms. Therefore, through DSJ control, the asymmetric flow under lateral conditions can be effectively corrected, expanding the flight envelope and enhancing the maneuverability and reliability of the aircraft.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"156 ","pages":"Article 109773"},"PeriodicalIF":5.0,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A preliminary investigation on a novel vortex-controlled flameholder for aircraft engine combustor","authors":"Yuling Zhao ,&nbsp;Jiadong Zhang ,&nbsp;Mingyu Li ,&nbsp;Bei Yu","doi":"10.1016/j.ast.2024.109723","DOIUrl":"10.1016/j.ast.2024.109723","url":null,"abstract":"<div><div>This study proposes a novel vortex-controlled flameholder (VCF) to enhance the combustion performance, particularly the lean ignition and blowout characteristics of afterburners in advanced aircraft engines across a wide range of operating conditions. Additionally, both experimental and numerical investigations were conducted to explore the effects of the cavity structure on the flow field, lean ignition, lean blowout, flame propagation characteristics, and outlet temperature rise distribution of the flameholder. Two distinct cavity structures designated closed-cavity (case-1) and open-cavity (case-2) were examined, the findings indicating that both case-1 and case-2 can generate large-scale vortex flow structures within the cavity, contributing to achieving excellent combustion stability. Case-2 demonstrated better lean ignition and blowout performance compared to case-1. Furthermore, both case-1 and case-2 exhibited the same ignition process, which comprised four distinct phases: Phase 1 involved the formation of an effective flame kernel; Phase 2 pertained to the ignition of the entire cavity by the flame kernel; Phase 3 represented the full development of the flame downstream of the cavity; Phase 4 described the formation of a fire tornado that anchors the flame front. Interestingly, the outlet temperature rise in case-1 is lower than that in case-2 at low fuel-to-air ratio (FAR) conditions. As the FAR increases, the difference in the outlet temperature rises between the two cases gradually narrows.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109723"},"PeriodicalIF":5.0,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142696820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic programming method for satellite optimization design with quantification of multi-granularity model uncertainty","authors":"Shucong Xie,&nbsp;Yunfeng Dong,&nbsp;Zhihua Liang","doi":"10.1016/j.ast.2024.109764","DOIUrl":"10.1016/j.ast.2024.109764","url":null,"abstract":"<div><div>Utilizing digital tools for satellite optimization design is vital for supporting decision-making in the actual engineering of satellites. The higher the accuracy of the simulation model, the more precise the satellite performance evaluation, and the more valuable the optimization results. Traditional heuristic algorithms have been successful in optimizing satellite parameters but face challenges when dealing with component-level optimization of satellite composition and structure. To address this issue, this paper presents a genetic programming method for satellite optimization design with quantification of multi-granularity model uncertainty. It defines a multi-granularity simulation model for satellites and presents a method for quantifying model uncertainty. Building upon this foundation, it designs genetic programming tree structures and genetic operations, introducing granularity switching criteria to enable on-demand switching of model granularity. Furthermore, based on the correlation between satellite capabilities and subsystems, it defines an active crossover criterion at the subsystem level to expedite convergence speed further. Numerical simulation cases demonstrate the effectiveness of this method, which enables rapid optimization design of satellite component models, providing timely and efficient assistance for engineering applications.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"156 ","pages":"Article 109764"},"PeriodicalIF":5.0,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142721125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of turbulence adjoint method in sensitivity calculation and aerodynamic design optimization of turbomachinery cascades","authors":"Jiaqi Luo ,&nbsp;Jiaxing Li ,&nbsp;Yao Zheng ,&nbsp;Zhonghua Han ,&nbsp;Feng Liu","doi":"10.1016/j.ast.2024.109761","DOIUrl":"10.1016/j.ast.2024.109761","url":null,"abstract":"<div><div>Adjoint-based optimization faces the challenges from sensitivity accuracy when applying in design optimization of turbomachinery cascades with strong turbulence flow. In the study, sensitivities of aerodynamic parameters of different cascades are calculated using the discrete adjoint method, which are then used for design optimization of the cascades. The principles of adjoint method are firstly introduced and the procedures of sensitivity calculation using discrete adjoint method are described. Aerodynamic sensitivities of a high-pressure-turbine cascade and a controlled-diffusion compressor cascade are calculated by both the turbulence adjoint and constant-eddy-viscosity (CEV) adjoint methods. Through comparisons against the sensitivities by finite difference method, the improved accuracy in sensitivity calculation by turbulence adjoint method is demonstrated. Moreover, at the off-design condition of the compressor cascade with intensified turbulence flow, more improvements in sensitivity accuracy are gained. Finally, aerodynamic design optimizations of these two cascades are conducted. The results illustrate that more gains in performance improvements can be obtained by turbulence adjoint method, especially in the optimization of compressor cascade at the off-design condition. The impacts of aerodynamic shape optimization on performance variations of the cascades are addressed.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"156 ","pages":"Article 109761"},"PeriodicalIF":5.0,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance enhancement of ammonium dinitramide (ADN)-based thruster using coaxial dielectric barrier discharge","authors":"Fangyi Wang ,&nbsp;Gongxi Zhou ,&nbsp;Yuhong Deng ,&nbsp;Shaohua Zhang ,&nbsp;Xilong Yu","doi":"10.1016/j.ast.2024.109769","DOIUrl":"10.1016/j.ast.2024.109769","url":null,"abstract":"<div><div>To enhance the performance of conventional ADN-based catalytic ignition thrusters, a plasma-assisted thruster was developed employing coaxial cylinder electrodes within a 1N-class thruster configuration. Steady-state ignition tests conducted on the experimental bench, demonstrated high repeatability in an atmospheric environment. High-speed imaging and proper orthogonal decomposition (POD) analysis revealed that plasma reduced the pulsation energy of the first mode from 84.96% to 75.21%, improving flame stability and concentrating the flame in the upstream part of the combustion chamber, without propagating toward the nozzle. Experimental evolution spectra of H₂O, NH₃, and CO₂ were obtained through near-infrared (NIR) and mid-infrared (MIR) spectrometers to probe chemical dynamics. The peak radiation intensity of H₂O and NH₃ in the 1.6-2.4 μm range was observed to precede by about one second with plasma compared to the catalyst-only case. An increased radiation intensity ratio of H₂O/NH₃ in the presence of plasma indicated plasma's promotion of H₂O production and NH₃ consumption. Furthermore, the radiation intensity of CO₂ increased by approximately 100-fold in the plasma-assisted case, indicating accelerated chemical reactions and more complete combustion. These findings highlight the potential of plasma-assisted technologies to improve the efficiency of ionic liquid-based thrusters and provide a foundation for future advancements in plasma-assisted propulsion systems.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"156 ","pages":"Article 109769"},"PeriodicalIF":5.0,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of aerodynamic coefficients for multi-swept delta wings via a hybrid neural network","authors":"Moritz Zieher,&nbsp;Christian Breitsamter","doi":"10.1016/j.ast.2024.109762","DOIUrl":"10.1016/j.ast.2024.109762","url":null,"abstract":"<div><div>This study investigates the prediction capabilities of a hybrid neural network model for the aerodynamic coefficients of multiple swept delta wings, focusing on rapidly estimating coefficient slopes and aerodynamic characteristics. By leveraging a machine learning approach combining image classification and conventional feed-forward neural networks, the study aims to provide an efficient alternative to resource-intensive computational fluid dynamics simulations or wind tunnel experiments during the early design phases of aircraft. The training dataset is derived from existing wind tunnel measurements of multiple swept delta wing configurations with varying leading-edge sweeps, incorporating both baseline configurations and scenarios with deflected control surfaces and applied sideslip angles. Parameters such as Mach number, Reynolds number, aspect ratio, angle of attack, angle of sideslip, and control surface deflections are considered additional input variables, representing a comprehensive range of flow conditions encountered in practical aerodynamic analyses. The findings demonstrate that the proposed hybrid neural network effectively predicts aerodynamic coefficients with high accuracy in forecasting lift coefficients and their derivatives. While the model exhibits excellent predictive performance for the trends in coefficient slopes, it shows limitations in accurately predicting the absolute values of pitching moment coefficients. Overall, the results underscore the potential of machine learning techniques for rapidly evaluating aerodynamic characteristics and slope trends, offering significant time and cost savings in preliminary aircraft design.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"156 ","pages":"Article 109762"},"PeriodicalIF":5.0,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Secure model predictive static programming with initial value generator for online computational guidance of near-space vehicles","authors":"Yuan-Zhuo Wang ,&nbsp;Hong-Hua Dai","doi":"10.1016/j.ast.2024.109768","DOIUrl":"10.1016/j.ast.2024.109768","url":null,"abstract":"<div><div>For online trajectory programming of near-space vehicles with limited computation resources, conventional model predictive static programming approaches have two main challenges. Firstly, an inadequate initial control guess can lead to trajectory divergence or slow convergence, resulting in mission failure. Secondly, Euler discretization is a small-step local algorithm by point-to-point recursion. To ensure high precision solution, more discretization points are required, leading to low computation efficiency and accuracy; meanwhile conventional methods cannot guarantee that the problems are solved within the constraints and feasible domains, potentially affecting the solution stability. To solve the first problem, a variable coefficient near-optimal initial value generator is developed to provide an initial control guess that approximates the optimal trajectory, preventing divergence in subsequent iterations. To address the second problem, the trust-region constrained model predictive static programming is proposed with flipped-Radau pseudospectrum. This method reduces the number of discretization points and optimizes the performance index directly, thereby enhancing efficiency; meanwhile the trust region improves accuracy and ensures the updated trajectory remains close to the reference trajectory. Finally, the combination of above approaches enhances the calculating efficiency and precision significantly for online trajectory programming. Applied to a near-space vehicle, the proposed method reduces optimization time by 25 % for rapid and high-precision solutions, and improves terminal position accuracy from 43 m to 1 m with flipped-Radau pseudospectrum.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"156 ","pages":"Article 109768"},"PeriodicalIF":5.0,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization flutter response of laminated smart nanocomposite truncated conical shell under supersonic aerodynamic pressure using hybrid IGWO-DQHFEM","authors":"L. Shan ,&nbsp;M. Furjan ,&nbsp;R. Kolahchi ,&nbsp;M. Yaylacı","doi":"10.1016/j.ast.2024.109766","DOIUrl":"10.1016/j.ast.2024.109766","url":null,"abstract":"<div><div>Given the wide application of conical shells in the aerospace and aircraft industry, there comes a need for dynamic analysis and optimum design of these structures against supersonic aerodynamic forces, which induce a phenomenon called flutter. As the key contribution of this paper, a new method has been developed and applied to optimize the dynamic and flutter control of truncated conical shells under supersonic aerodynamic loads. Here, a truncated conical shell with a layered configuration is considered for the optimization of supersonic aerodynamic conditions with smart control, shape, and size optimum design, wherein every layer is reinforced with carbon nanotubes (CNTs). Moreover, a conical shell is considered with piezoelectric properties to smartly control the aerodynamic behavior of the structure, so by applying voltage, it will be possible to control flutter or critical aerodynamic pressure and frequency. The objective of the optimization model is defined based on aerodynamic pressure and frequency of conical shells. Mathematical modeling of the structure with high accuracy is carried out to optimize the model. The supersonic aerodynamic force is considered employing piston theory, where seven variables are used through a high-order shear deformation theory. In the new numerical method, the differential quadrature hierarchical finite element method (DQHFM) is used for the solution of the coupled electro- dynamic equations of the structure and computing the frequency of the structure along with the flutter or critical aerodynamic pressure. The optimization model obtained by the DQHFM method is applied to search the optimum conditions using an Improved Grey Wolf Optimization (IGWO) method. In IGWO, the local search condition is proposed based on the optimum positions and statistical properties of agents in previous positions. Finally, the optimum size, shape, and smart control parameters of the structure such as the length and radius of the cone, cone apex angle, external voltage, CNTs volume fraction, number of layers, and airflow angle are drawn out and discussed by IGWO and DQHFM. The results show that by increasing the cone angle from 30 ^o to 60 ^o, the optimum voltage that has to be applied decreases. On the other hand, an optimal radius stabilizes at around 1 m and the optimum volume fraction of the CNTs is 10 %.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"156 ","pages":"Article 109766"},"PeriodicalIF":5.0,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the impact of vector thrust on aircraft maneuverability utilizing bypass dual throat nozzle technology","authors":"Jinglei Xu ,&nbsp;Rui Gu ,&nbsp;Shuai Huang","doi":"10.1016/j.ast.2024.109765","DOIUrl":"10.1016/j.ast.2024.109765","url":null,"abstract":"<div><div>With the progressive maturation of fluidic Thrust Vectoring technology, future advanced fighter aircraft are poised to adopt the new nozzle with higher vector efficiency. This research paper introduces an innovative analytical framework that seamlessly integrates nonlinear aircraft dynamics with thrust vectoring nozzles. An F-16 aircraft model and a bypass dual throat nozzle (BDTN) are introduced to analyze the impact of thrust vectoring on flight performance. Key findings indicate that thrust vectoring nozzles significantly enhance aircraft climb performance, resulting in a notable 28.1% increase in climb rate. Furthermore, the flow losses associated with these nozzles have minimal influence on the aircraft's kinematic state, with a mere 4.2% impact on mechanical energy within 10 s under a 20% thrust loss scenario. For thrust-vectored models performing maneuvers at a given pitch rate, a critical velocity threshold emerges. Above or equal to this threshold, thrust vectoring augments aircraft maneuverability; however, velocities below this threshold may lead to airspeed loss and increased risk of stall, emphasizing the delicate balance necessary for optimal performance. Lastly, the study reveals that during complex maneuvers, thrust vectoring enhances the aircraft's sideslip capability, further underlining its significance in enhancing overall flight performance.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"156 ","pages":"Article 109765"},"PeriodicalIF":5.0,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Autonomous numerical predictor-corrector guidance for human Mars landing missions","authors":"Youngro Lee,&nbsp;David D. Lee,&nbsp;Bong Wie","doi":"10.1016/j.ast.2024.109755","DOIUrl":"10.1016/j.ast.2024.109755","url":null,"abstract":"<div><div>The numerical predictor-corrector guidance method with a linear bank angle parameterization has been widely applied to various atmospheric entry guidance problems. However, it has been found that the linear bank angle approach has limitations in satisfying the final state requirement of a specific type of atmospheric entry mission. In response, this paper proposes a novel bank angle parameterization based on a logistic function, which improves the energy preservation capability and increases the potential final altitude at the end of the entry phase. The paper also suggests a guideline to determine a guidance law activation point for better entry performance. Numerical simulations demonstrate that the proposed guidance scheme outperforms the linear bank profile approach and is suitable for future human Mars landing missions.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"156 ","pages":"Article 109755"},"PeriodicalIF":5.0,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}