Aerospace Science and Technology最新文献

{"title":"Control allocation optimization for an over-actuated tandem tiltwing eVTOL aircraft considering aerodynamic interactions","authors":"","doi":"10.1016/j.ast.2024.109595","DOIUrl":"10.1016/j.ast.2024.109595","url":null,"abstract":"<div><div>This paper describes control allocation strategies for a tandem tiltwing electric vertical take-off and landing (eVTOL) aircraft with distributed propulsion. The control mappings are constructed as local surrogate models that relate the control effectors to the aircraft's aeropropulsive forces and moments across the full flight envelope, including interactional aerodynamics effects. Control allocation optimization problems are formulated based on force and moment commands for specific flight conditions. Specifically, a nonlinear programming formulation based on nonlinear control mapping is proposed for control allocation optimization, and the problem is solved using a sparse nonlinear optimizer. The solutions obtained from different formulations such as the minimization of force and moment residuals and the minimization of control effort are investigated. Furthermore, these solutions are compared with the solutions obtained using linear control mapping-based formulations. Results presented for the cases of forward flight, low speed flight &amp; hover, and flight in the transition corridor suggest that considering aerodynamic interactions while formulating and solving the control allocation problem is necessary for higher levels of accuracy compared to linear approaches. One-propeller-out scenarios and moment and force generation cases are also investigated. Finally, control allocation for steady and accelerated operation in the transition corridor is discussed. The contribution of the methods and results in the paper is a nonlinear control allocation methodology for the entire flight envelope of an over-actuated tandem tiltwing eVTOL aircraft.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315826","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":"Sensor placement for optimal aerodynamic data fusion","authors":"","doi":"10.1016/j.ast.2024.109598","DOIUrl":"10.1016/j.ast.2024.109598","url":null,"abstract":"<div><div>Aircraft design is recently evolving towards a digital twin representation that involves many heterogeneous data sources. The aerodynamic development of aircraft usually incorporates data from computational fluid dynamics simulations, wind tunnel testing, and flight tests. All of these data sources have their advantages and disadvantages, which can optimally be combined using data fusion methods. However, the quality of the data fusion result strongly depends on the experimental design, i.e. the placement of discrete sensors. Therefore, an optimized sensor placement is essential for data fusion applications, as the number of sensors is limited. This work presents a sensor placement strategy for the widely used Gappy proper orthogonal decomposition data fusion methodology. The sensor placement relies on a Bayesian formulation of the data fusion, allowing accurate error estimates. Based on the Bayesian posterior, a utility function characterizes the quality of the fused result by quantifying the expected information gain for the proper orthogonal decomposition coefficients. As the optimization of the sensor locations involves a complex combinatorial problem, we introduce an efficient genetic algorithm for this task. The method is demonstrated on a two-dimensional airfoil and the NASA Common Research Model with synthetic measurement errors. For both test cases, an optimal sensor placement results in smaller reconstruction errors than a conventional layout. The Bayesian approach leads, in most cases, to more accurate reconstructions and is more versatile than other well-established sensor placement methods. The proposed genetic algorithm finds better optima with significantly fewer function evaluations than the widely used greedy algorithms.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1270963824007272/pdfft?md5=7453abb6433b5af389afc209b4f12e63&pid=1-s2.0-S1270963824007272-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311760","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":"Derivation of analytic formulae for several resonance frequencies of the SparkJet actuator","authors":"","doi":"10.1016/j.ast.2024.109600","DOIUrl":"10.1016/j.ast.2024.109600","url":null,"abstract":"<div><div>Building on previous research that emphasized the importance of focusing on resonance frequencies for a fundamental understanding of the thrust and complex internal flow phenomena of the SparkJet actuators, this study theoretically derives analytic formulae for several important resonance frequencies. The research addresses the typical configuration of the SparkJet actuators, which consists of a cylindrical cavity and orifice connected by a conical converging nozzle. While the resonance frequencies of the SparkJet actuators can be obtained by solving the eigenvalue problem presented in previous studies, this eigenvalue problem, despite being a typical boundary value problem in the form of an elliptic partial differential equation, is challenging to solve using conventional numerical methods such as iterative methods, because the eigenvalue is included as an unknown in the operator. Consequently, Boundary Element Method (BEM) or methods using the Green functions have been proposed to obtain numerical solutions, but these still require handling large matrix data, resulting in significant computational costs and memory consumption. To overcome this, the current study first simplifies the eigenvalue problem using the conformal mapping presented in previous research. Then, referencing prior studies that claim that three types of resonance frequencies (Helmholtz resonance frequency and resonance frequencies representing streamwise or radial directional oscillation) significantly affect the thrust of the SparkJet actuators, characteristics of these frequencies are mathematically defined. Using these mathematical characteristics, the study derives the asymptotic and approximate solutions of the simplified eigenvalue problem, from which the resonance frequencies are obtained. The analytic formulae proposed in this study theoretically explain the already known geometric tendencies of the resonance frequencies and reveal new geometric factors influencing resonance frequencies, which were previously unknown. This approach is expected to facilitate obtaining several important resonance frequencies of the SparkJet actuator more promptly and accurately and to provide a deeper understanding of the nature of the complex oscillation phenomena inside the actuator.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311767","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":"An improved wiener filter-based method for identifying stall inception of transonic compressor","authors":"","doi":"10.1016/j.ast.2024.109576","DOIUrl":"10.1016/j.ast.2024.109576","url":null,"abstract":"<div><p>The development of the modern aviation industry poses high demands on the design of aircraft engines recently. However, the stability of compressor flow is one of the key factors affecting further improvements in engine performance. The design of next-generation aircraft engines imposes higher requirements on compressor loading, which leads to the emergence of many new stall inceptions. As a result, the onset and evolution of flow instability become more complex. For accurately capturing stall inceptions of transonic compressors, the strong pressure disturbances caused by shock waves at the blade tip and the complex flow within blade passages result in significant challenges. To address this issue, this study draws inspiration from the design methods of Wiener filters in the field of speech recognition. Based on the characteristic signal mutations during rotating stall in compressors, a Wiener filter approach that uses time-delayed signals as noise estimates during filter training is developed. The method can be used for both offline and online analysis. It was applied to analyze the stall signals of a single rotor from a 1.5-stage transonic axial compressor under distorted inlet conditions at transonic rotational speeds and the entire stage under uniform inlet conditions at subsonic rotational speeds. The results indicate that, under inlet distortion, the compressor generates disturbance signals in the distorted sector before stall, and the earliest spike-inception disturbance occurs at the circumferential position of the rotor leaving the distorted sector. Under uniform inlet conditions, random disturbances could be detected throughout the circumference before stall onset, developing into spike waves at a circumferential location that subsequently triggered stall. Compared to conventional low-pass filters, discrete wavelet transforms, and empirical mode decomposition, the Wiener filter yielded more prominent spike wave structures in the filtered signals. Under distorted inlet conditions, the Wiener-filtered signals showed a 1 % decrease in autocorrelation coefficient and a 3.7 % increase in root mean square (RMS) upon the appearance of spike waves, more pronounced than the 0.5 % decrease in autocorrelation coefficient and 1.8 % increase in RMS achieved by conventional methods. Under uniform inlet conditions, the Wiener filter also detected a 9.7 % increase in RMS upon the appearance of spike waves, more pronounced than the 6.3 % increase observed with conventional methods.</p></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240416","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":"Design of a locally resonant system to reduce noise inside the payload fairing of a launcher during the lift-off","authors":"","doi":"10.1016/j.ast.2024.109592","DOIUrl":"10.1016/j.ast.2024.109592","url":null,"abstract":"<div><p>The high sound pressure exerted on the payload during the launch of space vehicles can jeopardize its structural integrity. Given space and weight restrictions, designing fairing noise protection systems is not easy and the number of alternatives is limited, especially for small launchers. This work proposes the design of an acoustic protection based on an simultaneous increase of insulation and absorption in the system tailored to the payload fairing of a space launcher. To this end, the use of a panel made of Helmholtz resonators is investigated. The panel presents a deep subwavelength thickness, as well as a highly efficient acoustic protection (90% of absorption and 13 dB of Transmission Loss) over the frequency range of interest. The panel is designed by considering a reciprocal and non mirror symmetric transmission problem and the acoustic incidence from both sides of the panel. A high Transmission Loss in the frequency range of interest is then obtained when considering an incidence coming from the outside of the payload fairing, whereas the quasi-perfect absorption of acoustic waves is observed in the case where the incidence comes from the inside of the fairing. The panels are subsequently prototyped and their performance is experimentally evaluated. Measurements are correlated and discussed in view of the theoretical and numerical predictions. This mitigation approach sets a new trajectory for innovative noise reduction in small-scale space launchers.</p></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240420","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":"An efficient tracking differentiator based active disturbance rejection control for flight environment simulation system","authors":"","doi":"10.1016/j.ast.2024.109578","DOIUrl":"10.1016/j.ast.2024.109578","url":null,"abstract":"<div><div>The flight environment simulation system plays a crucial role in aeroengine testing, replicating real mission pressure and temperature conditions. However, existing systems face challenges in handling strong measurement noises and total disturbances during transient tests, leading to inaccurate simulations and potential actuator damage. To address these gaps, an enhanced tracking differentiator based active disturbance rejection control scheme is proposed and implemented. Our method introduces two key innovations: a discrete-time optimal control law that dynamically adjusts control inputs based on state transition and sampling times, and a phase-advancing method that mitigates filtering phase delays by incorporating derivative signals to predict input trends. These components are integrated into a novel tracking differentiator, enhancing the estimation capability of the extended state observer in active disturbance rejection control. Frequency-domain analysis demonstrates the proposed tracking differentiator's superior filtering performance and phase quality. Simulations of intake environment pressure during aeroengine transient tests reveal that, compared to traditional tracking differentiator-based active disturbance rejection control, the proposed approach significantly reduces both control signal oscillations and setpoint deviations by 75.44% and 53.9%, respectively. These improvements effectively address environment simulation deviations and unnecessary actuator wear, thereby enhancing the accuracy and reliability of aeroengine testing.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311758","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":"Compression response and optimization design of a novel glass-sponge inspired lattice structure with enhanced energy absorption capacity","authors":"","doi":"10.1016/j.ast.2024.109582","DOIUrl":"10.1016/j.ast.2024.109582","url":null,"abstract":"<div><div>Lattice structures have shown tremendous prospects in engineering fields, because of the ultralight, strong and toughness properties. In this paper, a novel configuration of lattice structure (GSIBCC) inspired by the hierarchical skeleton system of glass sponges is proposed. The new configuration of the unit cell is based on modifying the inner cross struts of the body-centered cubic (BCC) lattice, by considering the double diagonal reinforcements and hybridization of unit cells. The compression properties and deformation mechanism of the GSIBCC lattice structure are compared with BCC, OCT (Octet) and other glass sponge inspired lattices. A multi-objective optimization method is established, for maximizing the specific energy absorption (SEA) and simultaneously reducing the compression strength. The novel GSIBCC lattice exhibits superior specific energy absorption than BCC, OCT, and other glass sponge inspired lattices. For example, GSIBCC shows maximum 145.06% improvement (<span><math><mover><mi>ρ</mi><mo>¯</mo></mover></math></span>=0.124) of SEA with respect to BCC, and maximum 117.4% improvement (<span><math><mover><mi>ρ</mi><mo>¯</mo></mover></math></span>=0.124) of SEA with respect to OCT. The novel lattice exhibits the whole deformation type and obvious second stress reinforcement effect. Besides, the mechanical properties of GSIBCC are further improved using the multi-objective optimization. The reported biomimicry design strategy, deformation and failure mechanism, and multi-objective optimization method will be beneficial for enriching the lattice system and promoting the multifunctional applications of lattice structures in engineering fields.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311647","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":"Formation of leading vortex ring in the starting jet with background crossflow","authors":"","doi":"10.1016/j.ast.2024.109590","DOIUrl":"10.1016/j.ast.2024.109590","url":null,"abstract":"<div><p>The influence of background crossflow on the formation process of leading vortex ring in starting jet has been systematically investigated over the range of <span><math><mn>1</mn><mo>≤</mo><msub><mrow><mi>R</mi></mrow><mrow><mi>v</mi></mrow></msub><mo>≤</mo><mn>6</mn></math></span> and <span><math><mn>0.7</mn><mo>≤</mo><mi>L</mi><mo>/</mo><mi>D</mi><mo>≤</mo><mn>6</mn></math></span>, where <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>v</mi></mrow></msub></math></span> is the ratio of jet velocity to crossflow velocity and <span><math><mi>L</mi><mo>/</mo><mi>D</mi></math></span> is the ratio of jet column length to diameter. Particular attention is being paid to the unique interaction between the leading vortex ring and the trailing vortex structures. In general, the background crossflow disrupts the normal formation process of leading vortex ring by either stopping its growth prematurely (<span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>v</mi></mrow></msub><mo>≥</mo><mn>2</mn></math></span>) or preventing it from formation entirely (<span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>v</mi></mrow></msub><mo>&lt;</mo><mn>2</mn></math></span>). For <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>v</mi></mrow></msub><mo>≥</mo><mn>2</mn></math></span>, a new line, denoted as the optimal curve, is proposed with the formation number to illustrate the optimal application characteristics. The formation number diminishes with decreasing <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>v</mi></mrow></msub></math></span>. The mechanisms responsible for the clockwise (<span><math><mi>L</mi><mo>/</mo><mi>D</mi><mo>&gt;</mo><mi>L</mi><mo>/</mo><msub><mrow><mi>D</mi></mrow><mrow><mi>t</mi><mi>r</mi><mi>a</mi><mi>n</mi></mrow></msub></math></span>) and anticlockwise (<span><math><mi>L</mi><mo>/</mo><mi>D</mi><mo>&lt;</mo><mi>L</mi><mo>/</mo><msub><mrow><mi>D</mi></mrow><mrow><mi>t</mi><mi>r</mi><mi>a</mi><mi>n</mi></mrow></msub></math></span>) rotations of leading vortex ring have been further analyzed via kinematics and vortex dynamics. <span><math><mi>L</mi><mo>/</mo><msub><mrow><mi>D</mi></mrow><mrow><mi>t</mi><mi>r</mi><mi>a</mi><mi>n</mi></mrow></msub></math></span> represents the <span><math><mi>L</mi><mo>/</mo><mi>D</mi></math></span> corresponding to the transition of leading vortex ring from anticlockwise rotation to clockwise rotation. As for the inability to produce a complete leading vortex ring at <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>v</mi></mrow></msub><mo>&lt;</mo><mn>2</mn></math></span>, it is largely due to the fact that the crossflow weakens and directly inhibits the roll-up for the shear layer of starting jet on the windward side.</p></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240418","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":"Large eddy simulations of inlet temperature effects on the combustion instabilities in a partially premixed coaxial staged model combustor","authors":"","doi":"10.1016/j.ast.2024.109594","DOIUrl":"10.1016/j.ast.2024.109594","url":null,"abstract":"<div><p>To investigate the effects of inlet temperature on the combustion instability in a partially premixed coaxial staged model combustor, the Wall-Modeled Large Eddy Simulations and Flamelet Generated Manifolds are conducted for the combustion field structure and dynamic combustion characteristics at different inlet temperatures. The results show that the increasement of the inlet temperature leads to an enlargement of the axial size of the primary recirculation zone. Meanwhile, there is stronger velocity pulsation near the shear layer, but the temperature and heat release rate pulsation intensity at the shear layer weaken. With the increase of the inlet temperature, the flame anchor position shifts upstream, moving up by 10 mm from case 1 to case 2. This is because as the inlet temperature increases, the flow velocity rises for the same mass flow rate, resulting in stronger swirl in the pilot-stage. Consequently, the flame root transitions from the stabilized with main-stage swirl to the stabilized with pilot-stage swirl. The results of Fast Fourier Transfer and Dynamic Mode Decomposition reveal that there are two primary modes in the combustor, with frequencies of approximately 430 Hz and 1100 Hz. The results of the low-order thermoacoustic network indicate that as the inlet temperature increases from case 1 to case 2, the growth rate of the 430 Hz mode decreases from 4.5 rad s^-1 to -9.4 rad s^-1. This is also consistent with the gain trend of the flame transfer function, where, as the inlet temperature increases, the low-frequency gain decreases.</p></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240419","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 computational investigations of flexible membrane nano rotors in hover","authors":"","doi":"10.1016/j.ast.2024.109583","DOIUrl":"10.1016/j.ast.2024.109583","url":null,"abstract":"<div><div>With reduced size, the flight Reynolds number of the nano rotor decreases, leading to a sharp drop in the aerodynamic efficiency of the nano rotor. Therefore, improving the aerodynamic performance of the nano rotor at low Reynolds numbers through flow control methods becomes imperative. In this study, from the perspective of bionics, flexible materials are employed in nano rotor design. Seven different layouts of flexible membrane rotor blades are designed and fabricated. The influence of leading and trailing edge flexibility, as well as membrane occupancy ratio on rotor blade propulsion characteristics, is explored through propulsion performance tests in hover.</div><div>Results show that among several layouts proposed in this study, the layout with both reinforced leading and trailing edges of the flexible membrane nano rotor blade exhibits excellent propulsive performance. However, the propulsion performance of the flexible membrane rotors doesn't vary linearly with the ratio of membrane area to the whole rotor area. The appropriate ratio or flexibility can increase the propulsive performance of the rotor, especially at medium and high collective angles. At 7000 RPM and a 20° collective angle, the Figure of Merit of the flexible membrane nano rotor increases up to 4.2% when comparing with the nano rotor without membrane. This improvement becomes more significant with higher collective angles. The structural natural vibration characteristics of each flexible membrane with different layouts are analyzed through modal tests, ensuring the accuracy of the finite element model for flexible membrane rotors. Numerical analysis of the fluid-structure coupling of a flexible membrane rotor with different layouts indicates that rotor structural vibrations is highly consistent with fluctuation of aerodynamic parameters. The deformation of the flexible membrane under aerodynamic forces enhances local blade camber, but reduces angles of attack. This, subsequently, minimizes the size of laminar separation bubbles and the intensity of the blade tip vortices at high collective angles. Consequently, rotor power coefficients decrease, and overall aerodynamic performance improves.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311646","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}