Pub Date : 2025-02-03DOI: 10.1016/j.ast.2025.110014
Yunpeng Liu , Longchao Xu , Ronghui Cheng , Peng Guo , Yingwen Yan
The issue of combustion oscillations in bluff body diffusion flames within afterburners has received considerable attention. This study focuses on longitudinal mode oscillations of these flames. Through experiments, the dynamic response of the flame and self-sustained oscillations were examined. A validation from the experiment confirmed a coupling mechanism among velocity, pressure, and heat release rate oscillations. The results show that, despite the extended structure of the bluff body diffusion flame and significant phase differences in heat release rate pulsations across various flame regions, it is still reasonable to treat the flame as a point heat source. Using phase analysis, the study demonstrates how inlet conditions influence combustion oscillations. It also reveals that altering the bluff body structure can reduce the oscillation pressure amplitude by 64.5%. Therefore, modulating the dynamic response of the flame is key to mitigating combustion oscillations in afterburners, especially when the system's acoustic characteristics remain unchanged.
{"title":"Experimental study on phase transfer of longitudinal mode combustion oscillations in bluff body diffusion flames","authors":"Yunpeng Liu , Longchao Xu , Ronghui Cheng , Peng Guo , Yingwen Yan","doi":"10.1016/j.ast.2025.110014","DOIUrl":"10.1016/j.ast.2025.110014","url":null,"abstract":"<div><div>The issue of combustion oscillations in bluff body diffusion flames within afterburners has received considerable attention. This study focuses on longitudinal mode oscillations of these flames. Through experiments, the dynamic response of the flame and self-sustained oscillations were examined. A validation from the experiment confirmed a coupling mechanism among velocity, pressure, and heat release rate oscillations. The results show that, despite the extended structure of the bluff body diffusion flame and significant phase differences in heat release rate pulsations across various flame regions, it is still reasonable to treat the flame as a point heat source. Using phase analysis, the study demonstrates how inlet conditions influence combustion oscillations. It also reveals that altering the bluff body structure can reduce the oscillation pressure amplitude by 64.5%. Therefore, modulating the dynamic response of the flame is key to mitigating combustion oscillations in afterburners, especially when the system's acoustic characteristics remain unchanged.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"159 ","pages":"Article 110014"},"PeriodicalIF":5.0,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349063","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ast.2024.109865
Nicholas S. Reid, Robert A. Bettinger
In the past two years of 2023-2024, two space vehicles were inserted into orbits about Sun-Earth Lagrange points, joining eight other spacecraft about the and points. As interest in these points grows and become more populated, the chance for artificial space debris to inflict hazard on the region increases. The Circular Restricted Three-Body Problem (CR3BP) may be used to propagate the motion of debris in the region, and this paper investigates the risks associated with a catastrophic spacecraft breakup occurring in currently used or planned orbits about the Sun-Earth and points. The NASA Standard Breakup Model is used for debris generation, and a survivability model is used to calculate the debris related probability of hazard for a spacecraft with respect to a catastrophic breakup in the system. Additionally, a Monte Carlo simulation architecture enables a comprehensive sampling of initial conditions associated with potential breakup scenarios in the Sun-Earth and regions. Overall, this research finds that the maximum probability of hazard for a bystander spacecraft varies greatly on the order of to , based on different initial angular positions between the bystander and breakup spacecraft.
{"title":"Sun-Earth debris study, Part 2: Preliminary investigation of debris-induced spacecraft survivability risks near the Sun-Earth collinear Lagrange points","authors":"Nicholas S. Reid, Robert A. Bettinger","doi":"10.1016/j.ast.2024.109865","DOIUrl":"10.1016/j.ast.2024.109865","url":null,"abstract":"<div><div>In the past two years of 2023-2024, two space vehicles were inserted into orbits about Sun-Earth Lagrange points, joining eight other spacecraft about the <span><math><msub><mrow><mi>L</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>L</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> points. As interest in these points grows and become more populated, the chance for artificial space debris to inflict hazard on the region increases. The Circular Restricted Three-Body Problem (CR3BP) may be used to propagate the motion of debris in the region, and this paper investigates the risks associated with a catastrophic spacecraft breakup occurring in currently used or planned orbits about the Sun-Earth <span><math><msub><mrow><mi>L</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>L</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> points. The NASA Standard Breakup Model is used for debris generation, and a survivability model is used to calculate the debris related probability of hazard for a spacecraft with respect to a catastrophic breakup in the system. Additionally, a Monte Carlo simulation architecture enables a comprehensive sampling of initial conditions associated with potential breakup scenarios in the Sun-Earth <span><math><msub><mrow><mi>L</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>L</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> regions. Overall, this research finds that the maximum probability of hazard for a bystander spacecraft varies greatly on the order of <span><math><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>8</mn></mrow></msup></math></span> to <span><math><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>12</mn></mrow></msup></math></span>, based on different initial angular positions between the bystander and breakup spacecraft.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"157 ","pages":"Article 109865"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825351","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ast.2024.109859
Yiyuan Ma , Chaofan Wang , Zhonghua Han , Yue Wang
The growing demand for more efficient aircraft has made the development of innovative designs critical. Distributed propeller aircraft configurations are among the most promising solutions in this quest for enhanced performance. The objective of this study is to develop an efficient wing design and optimization methodology that accounts for the aerodynamic interaction between the propeller and wing during the aircraft's preliminary design phase. Traditional methods are often imprecise, relying on empirical methods to model wing-propeller interaction, or computationally intensive, using high-fidelity Computational Fluid Dynamics (CFD) methods unsuitable for the preliminary design phase. Therefore, a method that balances computational efficiency and accuracy is crucial. This research employs mid-fidelity methods and tools to design aircraft wings while considering aerodynamic interactions between the propeller and wing. After validating the methodology and framework, aerodynamic analyses are conducted on a regional propeller aircraft, including a study of potential Distributed Electric Propulsion (DEP) variants. The aerodynamic analysis shows that propeller-induced velocities improve lift distribution and reduce induced drag by 10.7%, enhancing the lift-to-drag ratio. In the tradeoff study of DEP configurations, the eight-propeller setup demonstrated a 6% longer range and reduced drag, with the wingtip-mounted propellers effectively mitigating wingtip vortex formation. These findings highlight the potential of DEP configurations to improve aerodynamic efficiency and aircraft range.
{"title":"Mid-fidelity aero-propulsive coupling approach for distributed propulsion aircraft","authors":"Yiyuan Ma , Chaofan Wang , Zhonghua Han , Yue Wang","doi":"10.1016/j.ast.2024.109859","DOIUrl":"10.1016/j.ast.2024.109859","url":null,"abstract":"<div><div>The growing demand for more efficient aircraft has made the development of innovative designs critical. Distributed propeller aircraft configurations are among the most promising solutions in this quest for enhanced performance. The objective of this study is to develop an efficient wing design and optimization methodology that accounts for the aerodynamic interaction between the propeller and wing during the aircraft's preliminary design phase. Traditional methods are often imprecise, relying on empirical methods to model wing-propeller interaction, or computationally intensive, using high-fidelity Computational Fluid Dynamics (CFD) methods unsuitable for the preliminary design phase. Therefore, a method that balances computational efficiency and accuracy is crucial. This research employs mid-fidelity methods and tools to design aircraft wings while considering aerodynamic interactions between the propeller and wing. After validating the methodology and framework, aerodynamic analyses are conducted on a regional propeller aircraft, including a study of potential Distributed Electric Propulsion (DEP) variants. The aerodynamic analysis shows that propeller-induced velocities improve lift distribution and reduce induced drag by 10.7%, enhancing the lift-to-drag ratio. In the tradeoff study of DEP configurations, the eight-propeller setup demonstrated a 6% longer range and reduced drag, with the wingtip-mounted propellers effectively mitigating wingtip vortex formation. These findings highlight the potential of DEP configurations to improve aerodynamic efficiency and aircraft range.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"157 ","pages":"Article 109859"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143134372","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ast.2024.109862
Victor Maldonado, Guilherme D. Fernandes, Aaron Mallory
Turbulent jets are produced by many propulsion systems containing a ducted fan or rotor operating at high speed. In this experimental study, the blades of a 12 cm diameter ducted rotor system were coated with a sharkskin-inspired surface with diverging tip micropillars. Surfaces containing 40 μm and 70 μm tall micropillars were applied on the rotor blades in order to study their role on fan aerodynamics and downstream jet flow. The ducted rotor was operated at up to 30,000 revolutions per minute (rpm), creating a turbulent jet with a Reynolds number of 5.97x105 and Mach number of 0.222 based on mean streamwise velocity. The inflow at the inlet of the rotor and the flow-field downstream was measured using high-speed laser Doppler velocimetry (LDV) techniques. The effect of the micropillar coatings on the rotor blades marginally increases the mean streamwise velocity and rotor figure of merit due to mitigating boundary layer separation at higher rotor speeds. Moreover, this occurs due to the micropillar's ability to increase wall-normal turbulence intensity in the boundary layer when the pillar height is scaled appropriately to the boundary layer thickness. The rotor hub and blade tip vortex structures become diffused and undergo breakup into smaller structures accompanied with an acceleration in the decay of absolute mean cross-stream vorticity. This quantity physically represents vortical structures with a lower magnitude of rotation. In a streamwise distance of 1.5 rotor diameters, the decay of mean cross-stream vorticity in the jet flow-field is 42.4% and 44.1% for the jets produced by the rotor blades coated with micropillars with h = 40 μm and 70 μm respectively. This is in comparison to the 38.1% cross-stream vorticity decay for the baseline jet generated by the ducted rotor coated with smooth kapton tape. However, it was found that the decay in turbulence intensity as well as turbulent kinetic energy is more localized near the inlet of the jet measurement domain, and becomes reorganized further downstream into circular-like contours along the jet centerline and path of the rotor hub vortex structures. The overall results indicate that shark-inspired surfaces are viable to enhance the operating efficiency of ducted fans for subsonic aircraft propulsion.
{"title":"Turbulence and vorticity decay of propulsion jets produced by ducted fans coated with a sharkskin-inspired surface","authors":"Victor Maldonado, Guilherme D. Fernandes, Aaron Mallory","doi":"10.1016/j.ast.2024.109862","DOIUrl":"10.1016/j.ast.2024.109862","url":null,"abstract":"<div><div>Turbulent jets are produced by many propulsion systems containing a ducted fan or rotor operating at high speed. In this experimental study, the blades of a 12 cm diameter ducted rotor system were coated with a sharkskin-inspired surface with diverging tip micropillars. Surfaces containing 40 μm and 70 μm tall micropillars were applied on the rotor blades in order to study their role on fan aerodynamics and downstream jet flow. The ducted rotor was operated at up to 30,000 revolutions per minute (rpm), creating a turbulent jet with a Reynolds number of 5.97x10<sup>5</sup> and Mach number of 0.222 based on mean streamwise velocity. The inflow at the inlet of the rotor and the flow-field downstream was measured using high-speed laser Doppler velocimetry (LDV) techniques. The effect of the micropillar coatings on the rotor blades marginally increases the mean streamwise velocity and rotor figure of merit due to mitigating boundary layer separation at higher rotor speeds. Moreover, this occurs due to the micropillar's ability to increase wall-normal turbulence intensity in the boundary layer when the pillar height is scaled appropriately to the boundary layer thickness. The rotor hub and blade tip vortex structures become diffused and undergo breakup into smaller structures accompanied with an acceleration in the decay of absolute mean cross-stream vorticity. This quantity physically represents vortical structures with a lower magnitude of rotation. In a streamwise distance of 1.5 rotor diameters, the decay of mean cross-stream vorticity in the jet flow-field is 42.4% and 44.1% for the jets produced by the rotor blades coated with micropillars with <em>h</em> = 40 μm and 70 μm respectively. This is in comparison to the 38.1% cross-stream vorticity decay for the baseline jet generated by the ducted rotor coated with smooth kapton tape. However, it was found that the decay in turbulence intensity as well as turbulent kinetic energy is more localized near the inlet of the jet measurement domain, and becomes reorganized further downstream into circular-like contours along the jet centerline and path of the rotor hub vortex structures. The overall results indicate that shark-inspired surfaces are viable to enhance the operating efficiency of ducted fans for subsonic aircraft propulsion.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"157 ","pages":"Article 109862"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143134006","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ast.2024.109841
Jianbin Ruan , Yinzhong Yan , Pu Xue , Yulong Li
Aerospace devices are vulnerable to pyroshock and require testing. The shock response spectrum (SRS) compares shock severity but ignores temporal features. To improve testing reliability, temporal characteristics and their changes during pyroshock propagation need to be studied. In this paper, the shock propagation problem is studied experimentally. Two temporal features, i.e., the effective duration and the initial rise time, are characterized by the moving mean square method. An appropriate window length is suggested based on the frequency analysis of the shock environment. The evolutions of the effective duration and the initial rise time are characterized and traced during shock propagation. The elastic wave mode of shock propagation is analyzed. It is found that shock propagates in structures mainly in the form of flexural mode. A temporal features prediction method based on traveling damped sine waves is also provided and validated by experimental results.
{"title":"Evolution of temporal features during pyroshock propagation caused by wave dispersion","authors":"Jianbin Ruan , Yinzhong Yan , Pu Xue , Yulong Li","doi":"10.1016/j.ast.2024.109841","DOIUrl":"10.1016/j.ast.2024.109841","url":null,"abstract":"<div><div>Aerospace devices are vulnerable to pyroshock and require testing. The shock response spectrum (SRS) compares shock severity but ignores temporal features. To improve testing reliability, temporal characteristics and their changes during pyroshock propagation need to be studied. In this paper, the shock propagation problem is studied experimentally. Two temporal features, i.e., the effective duration and the initial rise time, are characterized by the moving mean square method. An appropriate window length is suggested based on the frequency analysis of the shock environment. The evolutions of the effective duration and the initial rise time are characterized and traced during shock propagation. The elastic wave mode of shock propagation is analyzed. It is found that shock propagates in structures mainly in the form of flexural mode. A temporal features prediction method based on traveling damped sine waves is also provided and validated by experimental results.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"157 ","pages":"Article 109841"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143134225","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}
Compared to traditional aerodynamic control surfaces, the reaction control system (RCS) offers enhanced control maneuverability for hypersonic vehicles at high flight altitudes with a low-density effect. However, the interaction of double lateral jets in a rarefied nonequilibrium flow yields intricate flow phenomena, markedly affecting the performance analysis of RCS. In this study, the nonlinear coupled constitutive relations (NCCR) model, regarded as a promising and efficient approach for modeling rarefied nonequilibrium flows, is utilized to investigate the influence of double lateral jets on a typical hypersonic cone-cylinder vehicle at 80 km under different jet states. The results show that the low-pressure region aft of the first (auxiliary) jet exerts an attraction effect on the shock wave structure generated by the second (main) jet when both jets are active, altering the surface pressure distribution in the middle region. Specifically, the attraction effect reduces the high-pressure peak of the main jet, expands the area influenced by the wrapping effect, and disperses the disturbance of the wrapping effect on the wall, indicating that the implementation of an auxiliary jet at suitable positions can enhance the ejection process of the main jet and diminish the side effect of the RCS. Additionally, a lower surface pressure distribution especially near the jets is calculated using the NCCR model against NS equations, accentuating the influence of rarefied gas effect on lateral jet interactions. These findings highlight the engineering potential of the NCCR model for investigating complex flow phenomena behind multiple jets interaction in rarefied nonequilibrium crossflows, providing suitable calculation tools for the RCS design of hypersonic vehicles.
{"title":"Numerical assessment of double lateral jets interaction in rarefied nonequilibrium crossflows via nonlinear coupled constitutive relations","authors":"Junyuan Yang , Shuhua Zeng , Wenwen Zhao , Zhongzheng Jiang , Weifang Chen , Yunlong Qiu","doi":"10.1016/j.ast.2024.109851","DOIUrl":"10.1016/j.ast.2024.109851","url":null,"abstract":"<div><div>Compared to traditional aerodynamic control surfaces, the reaction control system (RCS) offers enhanced control maneuverability for hypersonic vehicles at high flight altitudes with a low-density effect. However, the interaction of double lateral jets in a rarefied nonequilibrium flow yields intricate flow phenomena, markedly affecting the performance analysis of RCS. In this study, the nonlinear coupled constitutive relations (NCCR) model, regarded as a promising and efficient approach for modeling rarefied nonequilibrium flows, is utilized to investigate the influence of double lateral jets on a typical hypersonic cone-cylinder vehicle at 80 km under different jet states. The results show that the low-pressure region aft of the first (auxiliary) jet exerts an attraction effect on the shock wave structure generated by the second (main) jet when both jets are active, altering the surface pressure distribution in the middle region. Specifically, the attraction effect reduces the high-pressure peak of the main jet, expands the area influenced by the wrapping effect, and disperses the disturbance of the wrapping effect on the wall, indicating that the implementation of an auxiliary jet at suitable positions can enhance the ejection process of the main jet and diminish the side effect of the RCS. Additionally, a lower surface pressure distribution especially near the jets is calculated using the NCCR model against NS equations, accentuating the influence of rarefied gas effect on lateral jet interactions. These findings highlight the engineering potential of the NCCR model for investigating complex flow phenomena behind multiple jets interaction in rarefied nonequilibrium crossflows, providing suitable calculation tools for the RCS design of hypersonic vehicles.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"157 ","pages":"Article 109851"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143134228","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ast.2024.109856
Yudong Hu , Zichu Liu , Chunwang Jiang , Wuxing Jing , Changsheng Gao
Aiming at the target's maneuver mode description problems in hypersonic vehicle defense, a maneuver mode parametric modeling method based on the trajectory curve evolution laws is proposed. Firstly, the longitudinal and lateral maneuver modes are investigated. To avoid the unobservability problem of the target's guidance law and dynamics model, the directly measurable target states are taken as the research object. Secondly, from the perspective of the trajectory curve evolution laws, the trajectory's curvature and torsion are extracted as the maneuvering characteristic parameters based on the differential geometry theory, which realizes the decoupling and dimensionality reduction among the maneuvering characteristic parameters. According to the trajectory characteristics of the hypersonic targets, the extracted curvature and torsion are decomposed into trend and period terms to prevent the mutual interference of different modal data. Finally, the trend term is described using the Autoregressive method. To address the periodic drift problem, the Time-Varying Autoregressive model is introduced to approximate the non-stationary characteristics of the periodic term, thereby improving modeling accuracy. By model superposition and combination with the curvilinear equations, the maneuver mode parametric model is obtained. Simulation results demonstrate that the established maneuver mode parametric model shares high consistency with the dynamic model.
{"title":"Maneuver mode parametric modeling based on trajectory curve evolution laws for hypersonic glide vehicles","authors":"Yudong Hu , Zichu Liu , Chunwang Jiang , Wuxing Jing , Changsheng Gao","doi":"10.1016/j.ast.2024.109856","DOIUrl":"10.1016/j.ast.2024.109856","url":null,"abstract":"<div><div>Aiming at the target's maneuver mode description problems in hypersonic vehicle defense, a maneuver mode parametric modeling method based on the trajectory curve evolution laws is proposed. Firstly, the longitudinal and lateral maneuver modes are investigated. To avoid the unobservability problem of the target's guidance law and dynamics model, the directly measurable target states are taken as the research object. Secondly, from the perspective of the trajectory curve evolution laws, the trajectory's curvature and torsion are extracted as the maneuvering characteristic parameters based on the differential geometry theory, which realizes the decoupling and dimensionality reduction among the maneuvering characteristic parameters. According to the trajectory characteristics of the hypersonic targets, the extracted curvature and torsion are decomposed into trend and period terms to prevent the mutual interference of different modal data. Finally, the trend term is described using the Autoregressive method. To address the periodic drift problem, the Time-Varying Autoregressive model is introduced to approximate the non-stationary characteristics of the periodic term, thereby improving modeling accuracy. By model superposition and combination with the curvilinear equations, the maneuver mode parametric model is obtained. Simulation results demonstrate that the established maneuver mode parametric model shares high consistency with the dynamic model.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"157 ","pages":"Article 109856"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143134067","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}
Effective geometric parameterization is crucial in aerodynamic shape optimization for enabling flexible surface deformation while maximizing design space coverage. This paper studies the impact of different geometric forms (closed and open curves) on the effectiveness of Proper Orthogonal Decomposition (POD) geometric parameterization and explores the information of physical features contained in the POD bases. The efficiency and design space coverage which are the main indicators of effectiveness. These indicators of two POD-based parameterization methods are tested on a hybrid database and four typical airfoils. The convergence of aerodynamic properties is also investigated in typical airfoils. In addition, a modified application criterion for POD bases is established by the recursive feature elimination method. A feature importance-based explainable AI (xAI) method is also developed, combining Shapley additive explanations (SHAP) and modified application criterion to explore the physical information contained in POD bases. The results indicate that the POD-based parameterization method constructed from open curves can reconstruct database with better efficiency and design space coverage. Additionally, compared to geometric errors, more POD bases may be required to cover the airfoil design space in order to achieve superior aerodynamic accuracy. Significant differences exist in the importance and correlation of POD bases derived from different geometric forms, with those from closed curves providing better reconstruction efficiency for geometric parameters.
{"title":"Impact of geometric forms on the effectiveness and physical features of POD-based geometric parameterization","authors":"Chenliang Zhang , Hongbo Chen , Xiaoyu Xu , Yanhui Duan , Guangxue Wang","doi":"10.1016/j.ast.2024.109776","DOIUrl":"10.1016/j.ast.2024.109776","url":null,"abstract":"<div><div>Effective geometric parameterization is crucial in aerodynamic shape optimization for enabling flexible surface deformation while maximizing design space coverage. This paper studies the impact of different geometric forms (closed and open curves) on the effectiveness of Proper Orthogonal Decomposition (POD) geometric parameterization and explores the information of physical features contained in the POD bases. The efficiency and design space coverage which are the main indicators of effectiveness. These indicators of two POD-based parameterization methods are tested on a hybrid database and four typical airfoils. The convergence of aerodynamic properties is also investigated in typical airfoils. In addition, a modified application criterion for POD bases is established by the recursive feature elimination method. A feature importance-based explainable AI (xAI) method is also developed, combining Shapley additive explanations (SHAP) and modified application criterion to explore the physical information contained in POD bases. The results indicate that the POD-based parameterization method constructed from open curves can reconstruct database with better efficiency and design space coverage. Additionally, compared to geometric errors, more POD bases may be required to cover the airfoil design space in order to achieve superior aerodynamic accuracy. Significant differences exist in the importance and correlation of POD bases derived from different geometric forms, with those from closed curves providing better reconstruction efficiency for geometric parameters.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"157 ","pages":"Article 109776"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143134072","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ast.2024.109772
Li Ding , Xingyu Liu , Rui Ma , Chao Tan , Ahmed Tijani Musa , Guibing Zhu , Yangmin Li , YaoYao Wang
This article explores robust adaptive motion control for a cable-driven aerial manipulator in the presence of input saturation. The investigation begins by considering the physical attributes of the aerial manipulator and establishing a kinematic and dynamic model of the system with lumped disturbances. Following this, a new control law is formulated using the parameter adaptive technique, where the adaptive law offers continuous estimation of the virtual parameters. Moreover, a Gaussian error function is utilized to tackle the challenge of input saturation. The stability of the controller proposed is confirmed using Lyapunov theory. Ultimately, numerical simulations and experimental comparisons are conducted to validate the accuracy and effectiveness of the proposed control strategy.
{"title":"Robust adaptive motion control for cable-driven aerial manipulators with input saturation","authors":"Li Ding , Xingyu Liu , Rui Ma , Chao Tan , Ahmed Tijani Musa , Guibing Zhu , Yangmin Li , YaoYao Wang","doi":"10.1016/j.ast.2024.109772","DOIUrl":"10.1016/j.ast.2024.109772","url":null,"abstract":"<div><div>This article explores robust adaptive motion control for a cable-driven aerial manipulator in the presence of input saturation. The investigation begins by considering the physical attributes of the aerial manipulator and establishing a kinematic and dynamic model of the system with lumped disturbances. Following this, a new control law is formulated using the parameter adaptive technique, where the adaptive law offers continuous estimation of the virtual parameters. Moreover, a Gaussian error function is utilized to tackle the challenge of input saturation. The stability of the controller proposed is confirmed using Lyapunov theory. Ultimately, numerical simulations and experimental comparisons are conducted to validate the accuracy and effectiveness of the proposed control strategy.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"157 ","pages":"Article 109772"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143134142","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ast.2024.109803
Dongliang Sun , Xiaolong Tang , Xiaoquan Yang , Jue Ding , Peifen Weng
To investigated the mechanism of flow loss occurs in gas-turbine exhaust volute, comprehensive analysis was conducted based on the traces of parametric optimizations. An original volute was parameterized by depicting the core-part with 6 parameters. Concerning the coefficients of total pressure loss and static pressure recovery, the volute was optimized, as a start of the investigation, by Particle Swarm Optimization (PSO) to generate 56 exhaust volute designs and 8 geometric parameter traces. The geometry evolution history was fully recorded by these traces during the optimization. Based on this, parameter sensitivity analyses were conducted by single, double and K-means-clustering-based comprehensive parameters. Furthermore, partial dependence plot (PDP) and individual conditional expectation plot (ICEP) were applied to enhance the expression of parameter sensitivity. This enables the detailed discussion of the mechanisms of flow loss occurs in exhaust volute. The results demonstrate that the Particle Swarm Optimization (PSO) algorithm is highly effective for optimizing the exhaust volute. After six rounds of optimization with eight particles per round, the total pressure loss coefficient at the exhaust volute outlet was reduced by 35%, while the static pressure recovery coefficient increased by 79%. The sensitivity analysis reveals that geometric parameters exhibit varying degrees of influence on aerodynamic performance, with diffuser length being the most critical factor. Notably, a shorter diffuser, constrained by the same external dimensions, tends to result in lower flow losses. Flow loss within the collector accounts for 71.7% of the total loss, which can be attributed to surface friction and turbulent dissipation. The latter is primarily driven by turbulent viscous dissipation, predominantly occurring in the collector section. Additionally, the size of large-scale vortices in the curved parts of the diffuser and collector, which contribute to turbulent dissipation, as well as the ratio of the average flow velocity to circulation speed in the collector, which affects wall friction, are key factors in flow loss generation.
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