Aerospace Science and Technology最新文献

{"title":"Drag dependency aspects in Hyperloop aerodynamics","authors":"Domenik Radeck ,&nbsp;João Nicolau ,&nbsp;Vladislav Kukharskii ,&nbsp;Lucía Ojer Guerra ,&nbsp;Felix Herkenrath ,&nbsp;Inés Velasco Martínez ,&nbsp;Jonathan Pflüger ,&nbsp;Agnes Jocher ,&nbsp;Christian Breitsamter","doi":"10.1016/j.ast.2024.109722","DOIUrl":"10.1016/j.ast.2024.109722","url":null,"abstract":"<div><div>The Hyperloop system is promising a viable solution for fast, sustainable, and economic travel between cities.</div><div>This paper investigates the challenging topic of Hyperloop aerodynamics via extensive numerical simulations. The study is divided based on the speed relative to the geometric Kantrowitz limit to manage the computational resources effectively. Below this limit, which marks the transition to choked flow, we conducted a cross-validation among an axisymmetric 2D model, a similar 3D geometry, and a realistic 3D geometry for blockage ratio 0.5 at several speeds. A definitive range for drag was determined, notably low absolute drag values were observed, and the 2D axisymmetric simplification was put into perspective.</div><div>Above the choked flow condition, we undertook two resource-intensive simulations of the 2D setup, accelerating through several kilometers of tube. This methodology allowed us to shed light on the drag behavior that emerges under transient conditions. The existence of three regimes outlined by literature is corroborated by our study. Nevertheless, distinct variations emerge between the analyses, notably in the configuration of the shock wave structure, the linear increment of drag at a constant velocity, and the influence of the pod's acceleration profile in the flow structure.</div><div>The study broadens the understanding of Hyperloop aerodynamics and offers realistic drag data for both choked and non-choked flow.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109722"},"PeriodicalIF":5.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664219","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":"Effects of the rotor tip gap on the aerodynamic and aeroacoustic performance of a ducted rotor in hover","authors":"Reinier J. Goudswaard,&nbsp;Daniele Ragni,&nbsp;Woutijn J. Baars","doi":"10.1016/j.ast.2024.109734","DOIUrl":"10.1016/j.ast.2024.109734","url":null,"abstract":"<div><div>Ducted rotors are configurations known to outperform their unducted reference baselines when aerodynamic performance is concerned. Aside from aerodynamic benefits in hover, a duct also affects acoustic emissions. One of the most contended design parameters of a duct-rotor assembly is the radial distance between the blade tip and the duct wall, referred to as the “tip gap”. The present study explains how the aerodynamic performance of a ducted-rotor system is affected by the tip-gap distance, taking into account the performance of the rotor and those of the duct's inlet lip and diffuser sections. Separate thrust measurements of the rotor and duct establish that the latter can generate up to half of the total thrust of the assembly. Static wall-pressure measurements along the inner wall of the duct reveal a low pressure suction zone over the duct's inlet lip area. This allows the assembly to generate more thrust than the rotor alone, even though the duct's diffuser section generates a drag component (negative thrust). From the velocity fields it is further shown that the performance-deterioration with an increasing tip gap distance is associated with a contraction of the rotor slipstream in the duct diffuser.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109734"},"PeriodicalIF":5.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664241","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":"Quasi-static compression response of a novel multi-step auxetic honeycomb with tunable transition strain","authors":"Shun Wang ,&nbsp;Hai-Tao Liu","doi":"10.1016/j.ast.2024.109730","DOIUrl":"10.1016/j.ast.2024.109730","url":null,"abstract":"<div><div>Auxetic honeycombs with multi-step deformation have received widespread attention due to their multifunctionality and superior mechanical properties. To improve the tunability of the auxetic honeycomb, a novel multi-step auxetic honeycomb (MSAH) is proposed by combining star-rhombic parts with crossed thin walls. MASH is characterized by multi-step deformation, and its stress-strain curve has three significant plateau stages. The strain during the transition between different deformation steps can be adjusted by designing unit cells with different geometrical parameters. In the compression process, the ordered contact of the cell walls of MASH is the critical reason for realizing the multi-step deformation. The quasi-static compression finite element model of MASH is established and verified by experiments. Quasi-static compression response and deformation mechanism of MASH are studied. Then, the effects of geometrical parameters on the compression response of MASH are investigated. The results show that the wall thickness has a greater effect on the compressive stress, and the cell-wall angle determines the deformation mode of MASH. Furthermore, the transition strain of MASH is theoretically analyzed and verified by numerical simulations. This study provides a reference for designing multi-step deformation honeycombs and applying multi-stage energy absorbers.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109730"},"PeriodicalIF":5.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664220","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":"Experimental and numerical characterization of E-glass/epoxy plain woven fabric composites containing void defects","authors":"Nagappa Siddgonde ,&nbsp;Vikas Kaushik ,&nbsp;Anup Ghosh","doi":"10.1016/j.ast.2024.109731","DOIUrl":"10.1016/j.ast.2024.109731","url":null,"abstract":"<div><div>The presence of voids in woven fabric composite (WFC) significantly affects the mechanical and thermomechanical properties. Void defects are introduced during the resin infiltration process due to various controlling parameters involved in the curing process, i.e., pressure, temperature, resin flow etc. In this study, the mechanical constants of 2D woven fabric composite were experimentally determined. A finite element (FE) based representative volume element (RVE) model has been validated against these experimental results. A multiscale-based FE model has been developed, and periodic boundary conditions are applied to the RVE model to evaluate the homogenized thermomechanical properties of WFC containing void defects. Present numerical model incorporates the geometrical microstructures of the post-cured woven composite and void contents obtained from X-ray microtomography. The influence of void defect and resin infiltration have been incorporated to evaluate the thermomechanical properties of plain WFC. A parametric study has been carried out with respect to the variation of void defects on thermoelastic properties of E-glass/epoxy plain WFC. The variation of void defects has been considered in micro and mesoscale models. Monte Carlo simulations further quantified the effects of void content on the thermomechanical constants of WFC. The presence of voids has been observed to have significant influences on the thermomechanical constants of yarn and woven fabric composites.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109731"},"PeriodicalIF":5.0,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664221","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":"Transient gas path fault diagnosis of aero-engine based on domain adaptive offline reinforcement learning","authors":"Jinghui Xu,&nbsp;Ye Wang,&nbsp;Zepeng Wang,&nbsp;Xizhen Wang,&nbsp;Yongjun Zhao","doi":"10.1016/j.ast.2024.109701","DOIUrl":"10.1016/j.ast.2024.109701","url":null,"abstract":"<div><div>Real-time measurement parameters are crucial for diagnosing faults in aero-engine gas path performance, ensuring engine reliability, and mitigating potential economic losses. Traditional aero-engines performance diagnosis was mainly based on the measurements of steady-state condition and lacked the utilization of data under transient conditions. Gas path diagnosis of aero-engines under transient conditions is crucial for early fault detection and safety of flight within the envelope. The challenge lies in the inconsistent distribution of performance deviations caused by variable operating conditions, especially with complex fault types, which can undermine diagnostic credibility. To improve reliability of gas path diagnosis under transient conditions, an offline reinforcement learning fault diagnosis framework based on a transient aero-engine performance model is proposed. To address the issue of variable operating conditions during transient states, a domain adaptive approach is utilized to reconstruct the measurement baseline and facilitate the transfer of different performance deviation distributions. Additionally, by adding spool acceleration as a measurement parameter, the multi-component fault coupling is solved. Finally, validation with actual operating data simulates fault cases, demonstrating the proposed method's efficacy in quantitatively detecting gradual, sudden, and multiple component faults under transient conditions with high accuracy and efficiency. The method proposed in this study achieves a computational speed improvement by 64% compared to the conventional method, achieving a time of 0.13 seconds, with an average error of less than 0.00389%. Additionally, it demonstrates strong robustness in the presence of noise, with an average error of less than 0.03125%. This proposed method improves real-time fault detection under transient conditions for its higher accuracy and efficiency, and therefore significantly enhance gas path health monitoring and diagnosis capability.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109701"},"PeriodicalIF":5.0,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664239","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":"Corrigendum to “Numerical Study of Cold Flow Characteristics of a New Integrated Afterburner with Strut Flame Stabilizer” [Aerospace Science and Technology 153C (2024) 109476]","authors":"Minqiang Li ,&nbsp;Zhiwu Wang ,&nbsp;Junlin Li","doi":"10.1016/j.ast.2024.109705","DOIUrl":"10.1016/j.ast.2024.109705","url":null,"abstract":"","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109705"},"PeriodicalIF":5.0,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664225","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":"Crashworthiness and stiffness improvement of a variable cross-section hollow BCC lattice reinforced with metal strips","authors":"Bo Li ,&nbsp;Hua Liu ,&nbsp;Qiao Zhang ,&nbsp;Chuanguo Chai ,&nbsp;Jie Wang ,&nbsp;Jialing Yang ,&nbsp;Xianfeng Yang","doi":"10.1016/j.ast.2024.109732","DOIUrl":"10.1016/j.ast.2024.109732","url":null,"abstract":"<div><div>The ultra-lightweight structures with high mechanical properties and energy absorption behaviors are focused on the innovation structural design. The design strategy of implementing novel unit cells within architecture materials such as lattice materials enables the attainment of unparalleled combinations of mechanical properties and functionalities while minimizing weight. The most common method to design light-weight lattice materials is optimizing the geometric configurations of the unit cells. However, changing the geometric boundary of lattice structures can also be a good solution to improve the mechanical characteristics and energy absorption behaviors of the lattice materials. In this work, a novel variable cross-section hollow (VCH) lattice was established to improve the energy absorption capacity. By adding metal strips on the edge of the VCH lattices, a new reinforced variable cross-section hollow (RVCH) lattice with metal strips was developed to further enhance the stiffness and energy absorption capacity. The stainless VCH and RVCH lattices were additively manufactured by Selective Laser Melting (SLM) using an EP-M450H metal 3D printer. The quasi-static compressive characteristics and energy absorption behaviors of RVCH lattices were studied experimentally. Finite element modeling was implemented to study the energy absorption mechanism of RVCH lattices. A parametric analysis based on the finite element models was conducted to study the influence of different metal strips on the energy absorption capacity of RVCH lattices. The results show that the RVCH lattices with metal strips attaching to the vertical edges can signally enhance energy absorption of lattice structures with good load uniformity. Furthermore, the natural frequencies analysis indicate that the higher bending stiffness and the tensile stiffness can be achieved for RVCH lattices. This novel lattice is more stable as a load-bearing structure and more efficient as an energy absorber, which can provide guidance in designing innovative lattice structures with excellent mechanical properties and energy absorption capacity.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109732"},"PeriodicalIF":5.0,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664208","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":"Corrigendum to “External loads identification and shape sensing on an aluminum wing box: An integrated approach” [Aerospace Science and Technology 114 (2021) 106743]","authors":"Marco Esposito ,&nbsp;Marco Gherlone ,&nbsp;Pier Marzocca","doi":"10.1016/j.ast.2024.109707","DOIUrl":"10.1016/j.ast.2024.109707","url":null,"abstract":"","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109707"},"PeriodicalIF":5.0,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664224","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":"Fluid-thermal-structural coupled investigation on rudder leading edge with porous opposing jet in high-speed flow","authors":"Shaliang Li,&nbsp;Shibin Li,&nbsp;Wei Huang,&nbsp;Bing Liu","doi":"10.1016/j.ast.2024.109725","DOIUrl":"10.1016/j.ast.2024.109725","url":null,"abstract":"<div><div>High-speed air rudders face extreme force/thermal environments, and the opposing jet can improve the thermal environment in the stationary point and leading edge. In order to investigate the effect and mechanism of porous opposing jet on the rudder leading edge, the numerical study is carried out by using SST <em>k</em>-<em>ω</em> turbulence model and a loose fluid-thermal-structural coupled approach. The drag reduction and thermal protection mechanism of porous jet with different pressure ratios (<em>PRs</em>) is comprehensively compared and analyzed. The obtained results show that the fluid-thermal-structural coupled approach is necessary for the precise aerodynamic heat prediction of air rudder. The lowest temperature regions distribute in the upstream of orifices due to the jet cooling effect and heat conduction in the solid structure. The <em>PR</em> is an important factor influencing the interaction between jets. The porous opposing jet can provide a good effect in both drag reduction and thermal protection, as the maximum temperature drops to about 40 % from no jet to porous jet. As <em>PR</em> increases, the maximum pressure and temperature also decrease to a larger extent. However, the most <em>PR</em> should be a balanced consideration among the flowfiled, thermal structure and coolant consume.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109725"},"PeriodicalIF":5.0,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664240","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":"Aerodynamic study of a bifurcated turboprop engine inlet with a propeller for flow at ground suction conditions","authors":"Gaojie Zheng ,&nbsp;Zhenlong Wu ,&nbsp;Huijun Tan ,&nbsp;Jiahao Ren ,&nbsp;Yue Zhang ,&nbsp;Ge Zhou","doi":"10.1016/j.ast.2024.109720","DOIUrl":"10.1016/j.ast.2024.109720","url":null,"abstract":"<div><div>An advanced turboprop inlet with a bypass duct plays a crucial role in preventing foreign object damage and ensuring a high-quality airflow to the engine. However, it also introduces an increased flow complexity and design challenge due to the interaction between the propeller and the bifurcated ducts. To address these issues, a combined experimental and computational fluid dynamics (CFD) study was conducted on the aerodynamic performance and flowfield characteristics of a turboprop inlet equipped with a bypass duct considering the propeller interference. A ground suction test bench was utilized for generating the working conditions and the performance was measured by using total pressure rakes and pressure scanners. It is found that the rotational propeller on the one hand does work on and thus increases the total pressure recovery of the inlet, however, on the other hand causes a turning effect on the inlet flowfield structure along the direction of rotation and increases total pressure and swirling flow distortions in the engine duct. Besides, the engine duct and the bypass duct interact with each other. The combined influence of suction effect and the profile induction of the inlet leads to the majority of the shed vortices being drawn into the engine duct. Lastly, the presence of deflectors installed in the engine duct is found to effectively mitigate the secondary flow, thereby reducing the swirl distortion within the engine duct. This study may provide a significant reference to the design and optimization of advanced turboprop inlets with bypass ducts.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109720"},"PeriodicalIF":5.0,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664237","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}