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Recent Advances in Airfoil Self-Noise Passive Reduction 翼型自噪声被动降噪研究进展
IF 0.1 4区 工程技术
Aerospace America Pub Date : 2023-09-08 DOI: 10.3390/aerospace10090791
Behzad Amirsalari, Joana Rocha
{"title":"Recent Advances in Airfoil Self-Noise Passive Reduction","authors":"Behzad Amirsalari, Joana Rocha","doi":"10.3390/aerospace10090791","DOIUrl":"https://doi.org/10.3390/aerospace10090791","url":null,"abstract":"Airflow-induced noise prediction and reduction is one of the priorities for both the energy and aviation industries. This review paper provides valuable insights into flow-induced noise computation, prediction, and optimization methods with state-of-the-art efforts in passive noise reduction on airfoils, blades, and wings. This review covers the combination of several approaches in this field, including analytical, numerical, empirical, semi-empirical, artificial intelligence, and optimization methods. Under passive noise reduction techniques, leading and trailing edge treatments, porous materials, controlled diffusion airfoils, morphing wings, surface treatments, and other unique geometries that researchers developed are among the design modification methods discussed here. This work highlights the benefits of incorporating multiple techniques to achieve the best results concerning the desired application and design. In addition, this work provides an overview of the advantages and disadvantages of each tool, with a particular emphasis on the possible challenges when implementing them. The methods and techniques discussed herein will help increase the acoustic efficiency of aerial structures, making them a beneficial resource for researchers, engineers, and other professionals working in aviation noise reduction.","PeriodicalId":50845,"journal":{"name":"Aerospace America","volume":"102 5 Suppl E 1","pages":""},"PeriodicalIF":0.1,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89670227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Novel Digital Twin Framework for Aeroengine Performance Diagnosis 一种新型航空发动机性能诊断数字孪生框架
IF 0.1 4区 工程技术
Aerospace America Pub Date : 2023-09-08 DOI: 10.3390/aerospace10090789
Zepeng Wang, Ye Wang, Xizhen Wang, Kaiqiang Yang, Yongjun Zhao
{"title":"A Novel Digital Twin Framework for Aeroengine Performance Diagnosis","authors":"Zepeng Wang, Ye Wang, Xizhen Wang, Kaiqiang Yang, Yongjun Zhao","doi":"10.3390/aerospace10090789","DOIUrl":"https://doi.org/10.3390/aerospace10090789","url":null,"abstract":"Aeroengine performance diagnosis technology is essential for ensuring flight safety and reliability. The complexity of engine performance and the strong coupling of fault characteristics make it challenging to develop accurate and efficient gas path diagnosis methods. To address these issues, this study proposes a novel digital twin framework for aeroengines that achieves the digitalization of physical systems. The mechanism model is constructed at the component level. The data-driven model is built using a particle swarm optimization–extreme gradient boosting algorithm (PSO-XGBoost). These two models are fused using the low-rank multimodal fusion method (LWF) and combined with the sparse stacked autoencoder (SSAE) to form a digital twin framework of the engine for performance diagnosis. Compared to methods that are solely based on mechanism or data, the proposed digital twin framework can effectively use mechanism and data information to improve the accuracy and reliability. The research results show that the proposed digital twin framework has an error rate of 0.125% in predicting gas path parameters and has a gas path fault diagnosis accuracy of 98.6%. Considering that the degradation cost of a typical flight mission for only one aircraft engine after 3000 flight cycles is approximately USD 209.5, the proposed method has good economic efficiency. This framework can be used to improve engine reliability, availability, and efficiency, and has significant value in engineering applications.","PeriodicalId":50845,"journal":{"name":"Aerospace America","volume":"35 1","pages":""},"PeriodicalIF":0.1,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73230084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Characteristics of Vortices around Forward Swept Wing at Low Speeds/High Angles of Attack 低速/大迎角前掠翼涡特性研究
IF 0.1 4区 工程技术
Aerospace America Pub Date : 2023-09-08 DOI: 10.3390/aerospace10090790
Masahiro Kanazaki, Nao Setoguchi
{"title":"Characteristics of Vortices around Forward Swept Wing at Low Speeds/High Angles of Attack","authors":"Masahiro Kanazaki, Nao Setoguchi","doi":"10.3390/aerospace10090790","DOIUrl":"https://doi.org/10.3390/aerospace10090790","url":null,"abstract":"The forward-swept wing (FSW), one of the wing planforms used in aircraft, is known for its high performance in reducing wave drag. Additionally, a study has shown that this wing planform can mitigate sonic booms, which pose a significant challenge to achieving supersonic transport (SST). Therefore, FSW is expected to find applications in future SST aircraft owing to aerodynamic advantages at high speeds. However, there is a lack of sufficient knowledge and systematization to improve aerodynamic performance at low speeds and high angles of attack during takeoff and landing. These are crucial for practical implementation. Although the aerodynamic benefits of an FSW in high-speed flight can be harnessed using advanced structural and control technologies, the realization of SST using an FSW is challenging without enhanced research on low-speed aerodynamics. This study explores the practical aerodynamic knowledge of FSWs. We utilized a numerical simulation based on the Navier–Stokes equation and focused on investigating wake vortex phenomena. Our simulation included various wing planforms, including backward-swept wings (BSWs). The results revealed the presence of vortices with lateral axes emanating from the FSW, while longitudinal vortices were observed in the BSW. Based on these results, we developed a theoretical hypothesis for the vortex structure around an FSW.","PeriodicalId":50845,"journal":{"name":"Aerospace America","volume":"6 1","pages":""},"PeriodicalIF":0.1,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91244831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
GPU Acceleration of CFD Simulations in OpenFOAM GPU加速CFD模拟在OpenFOAM
IF 0.1 4区 工程技术
Aerospace America Pub Date : 2023-09-08 DOI: 10.3390/aerospace10090792
Federico Piscaglia, F. Ghioldi
{"title":"GPU Acceleration of CFD Simulations in OpenFOAM","authors":"Federico Piscaglia, F. Ghioldi","doi":"10.3390/aerospace10090792","DOIUrl":"https://doi.org/10.3390/aerospace10090792","url":null,"abstract":"We introduce algorithmic advancements designed to expedite simulations in OpenFOAM using GPUs. These developments include the following. (a) The amgx4Foam library, which connects the open-source AmgX library from NVIDIA to OpenFOAM. Matrix generation, involving tasks such numerical integration and assembly, is performed on CPUs. Subsequently, the assembled matrix is processed on the CPU. This approach accelerates the computationally intensive linear solver phase of simulations on GPUs. (b) Enhancements to code performance in reactive flow simulations, by relocating the solution of finite-rate chemistry to GPUs, which serve as co-processors. We present code verification and validation along with performance metrics targeting two distinct application sets, namely, aerodynamics calculations and supersonic combustion with finite-rate chemistry.","PeriodicalId":50845,"journal":{"name":"Aerospace America","volume":"33 1","pages":""},"PeriodicalIF":0.1,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76344035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Digital-Twin-Based Detection and Protection Framework for SDC-Induced Sinkhole and Grayhole Nodes in Satellite Networks 一种基于数字双子星的卫星网络sdc引起的天坑和灰洞节点检测与保护框架
IF 0.1 4区 工程技术
Aerospace America Pub Date : 2023-09-07 DOI: 10.3390/aerospace10090788
Gongzhe Qiao, Zhuang Yi, Tong Ye, Yuan Qiao
{"title":"A Digital-Twin-Based Detection and Protection Framework for SDC-Induced Sinkhole and Grayhole Nodes in Satellite Networks","authors":"Gongzhe Qiao, Zhuang Yi, Tong Ye, Yuan Qiao","doi":"10.3390/aerospace10090788","DOIUrl":"https://doi.org/10.3390/aerospace10090788","url":null,"abstract":"In the space environment, cosmic rays and high-energy particles may cause a single-event upset (SEU) during program execution, and further cause silent data corruption (SDC) errors in program outputs. After extensive research on SEU and SDC errors, it has been found that SDC errors in the routing program in satellite networks may lead to the emergence of Sinkhole (SH) and Grayhole (GH) nodes in the network, which may cause damage to satellite networks. To find and solve the problems in time, a digital-twin-based detection and protection framework for SDC-induced SH and GH nodes in satellite networks is proposed. First, the satellite network fault model under SEU and the generation mechanism of SH and GH nodes induced by SDC errors are described. Then, the data structure based on digital twins required by the proposed detection and protection framework is designed, and the detection methods of SH and GH nodes induced by SDC errors are proposed. SKT and LLFI simulation tools are used to build a simulated Iridium satellite network and carry out fault injection experiments. Experiment results show that the accuracy of the proposed detection method is 98–100%, and the additional time cost of routing convergence caused by the proposed framework is 3.1–28.2%. Compared with existing SH and GH detection methods, the proposed methods can timely and accurately detect faults during the routing update stage.","PeriodicalId":50845,"journal":{"name":"Aerospace America","volume":"51 1","pages":""},"PeriodicalIF":0.1,"publicationDate":"2023-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76653000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Progress in Redundant Electromechanical Actuators for Aerospace Applications 航天用冗余机电作动器研究进展
IF 0.1 4区 工程技术
Aerospace America Pub Date : 2023-09-07 DOI: 10.3390/aerospace10090787
F. Annaz, Malaka Miyuranga Kaluarachchi
{"title":"Progress in Redundant Electromechanical Actuators for Aerospace Applications","authors":"F. Annaz, Malaka Miyuranga Kaluarachchi","doi":"10.3390/aerospace10090787","DOIUrl":"https://doi.org/10.3390/aerospace10090787","url":null,"abstract":"The power to move aircraft control surfaces has advanced from being manually generated (by the pilot and transmitted via rods and links) to electrically transmitted (via wires) to operate control surface actuators. Various hydraulic, electromagnetic, and electromechanical architectures have been developed to provide the necessary power and to maintain the expected redundancy. Numerous aircraft actuator system designs have been proposed in the past decades, but a comprehensive review has yet to be undertaken. This review paper aims to fill this gap by providing a critical review of the actuation system designs developed for a variety of aircraft. The review focuses on aircraft actuator system designs, namely: electrohydraulic actuator systems, electromechanical actuator systems, and the force-fighting effect in redundant actuation systems. The significance and operational principle of each actuator system are critically analysed and discussed in the review. The paper also evaluates the solution proposed to address force-fight equalization (or force-fight cancelation) in force or torqued-summed architectures. Future trends in redundant actuation system development with reduced force-fighting effect in aircraft actuator systems are also addressed.","PeriodicalId":50845,"journal":{"name":"Aerospace America","volume":"10 1","pages":""},"PeriodicalIF":0.1,"publicationDate":"2023-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91075617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
L1 Adaptive Control Based on Dynamic Inversion for Morphing Aircraft 基于动态反演的变形飞行器L1自适应控制
IF 0.1 4区 工程技术
Aerospace America Pub Date : 2023-09-07 DOI: 10.3390/aerospace10090786
Lingquan Cheng, Yiyang Li, Jiayi Yuan, J. Ai, Yiqun Dong
{"title":"L1 Adaptive Control Based on Dynamic Inversion for Morphing Aircraft","authors":"Lingquan Cheng, Yiyang Li, Jiayi Yuan, J. Ai, Yiqun Dong","doi":"10.3390/aerospace10090786","DOIUrl":"https://doi.org/10.3390/aerospace10090786","url":null,"abstract":"Morphing aircraft are able to keep optimal performance in diverse flight conditions. However, the change in geometry always leads to challenges in the design of flight controllers. In this paper, a new method for designing a flight controller for variable-sweep morphing aircraft is presented—dynamic inversion combined with L1 adaptive control. Firstly, the dynamics of the vehicle is analyzed and a six degrees of freedom (6DOF) nonlinear dynamics model based on multibody dynamics theory is established. Secondly, nonlinear dynamic inversion (NDI) and incremental nonlinear dynamic inversion (INDI) are then employed to realize decoupling control. Thirdly, linear quadratic regulator (LQR) technique and L1 adaptive control are adopted to design the adaptive controller in order to improve robustness to uncertainties and ensure the control accuracy. Finally, extensive simulation experiments are performed, wherein the demonstrated results indicate that the proposed method overcomes the drawbacks of conventional methods and realizes an improvement in control performance.","PeriodicalId":50845,"journal":{"name":"Aerospace America","volume":"224 1","pages":""},"PeriodicalIF":0.1,"publicationDate":"2023-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80049808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Fatigue Reliability Analysis of Composite Material Considering the Growth of Effective Stress and Critical Stiffness 考虑有效应力和临界刚度增长的复合材料疲劳可靠性分析
IF 0.1 4区 工程技术
Aerospace America Pub Date : 2023-09-06 DOI: 10.3390/aerospace10090785
Jianxiong Gao, Fei Heng, Yi-Ping Yuan, Yuanyuan Liu
{"title":"Fatigue Reliability Analysis of Composite Material Considering the Growth of Effective Stress and Critical Stiffness","authors":"Jianxiong Gao, Fei Heng, Yi-Ping Yuan, Yuanyuan Liu","doi":"10.3390/aerospace10090785","DOIUrl":"https://doi.org/10.3390/aerospace10090785","url":null,"abstract":"Fatigue damage accumulation will not only cause the degradation of material performance but also lead to the growth of effective stress and critical stiffness. However, the existing fatigue reliability models usually ignore the effective stress growth and its influence on the critical stiffness of a composite material. This study considers the combined effects of performance degradation and effective stress growth, and a pair of fatigue reliability models for a composite material are presented. Firstly, the fatigue damage in a composite material is quantified by its performance degradation, and the fitting accuracy of several typical fatigue damage models is compared. Subsequently, the uncertainties of initial strength and initial stiffness are considered, and a pair of probabilistic models of residual strength and residual stiffness are proposed. The performance degradation data of Gr/PEEK [0/45/90/−45]2S laminates are utilized to verify the proposed probabilistic models. Finally, the effective stress growth mechanism and its influence on the failure threshold are elaborated, and a pair of fatigue reliability models for composite materials are developed. Moreover, the differences between the strength-based and stiffness-based reliability analysis results of composite materials are compared and discussed.","PeriodicalId":50845,"journal":{"name":"Aerospace America","volume":"19 1","pages":""},"PeriodicalIF":0.1,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84451713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Numerical Simulation of Transonic Compressors with Different Turbulence Models 不同湍流模式下跨声速压气机的数值模拟
IF 0.1 4区 工程技术
Aerospace America Pub Date : 2023-09-06 DOI: 10.3390/aerospace10090784
Wen‐Jing Yan, Zhaozheng Sun, Junwei Zhou, Kun Zhang, Jiahui Wang, Xiao Tian, Junqian Tian
{"title":"Numerical Simulation of Transonic Compressors with Different Turbulence Models","authors":"Wen‐Jing Yan, Zhaozheng Sun, Junwei Zhou, Kun Zhang, Jiahui Wang, Xiao Tian, Junqian Tian","doi":"10.3390/aerospace10090784","DOIUrl":"https://doi.org/10.3390/aerospace10090784","url":null,"abstract":"One of the most commonly used techniques in aerospace engineering is the RANS (Reynolds average Navier–Stokes) approach for calculating the transonic compressor flow field, where the accuracy of the computation is significantly affected by the turbulence model used. In this work, we use SA, SST, k-ɛ, and the PAFV turbulence model developed based on the side-biased mean fluctuations velocity and the mean strain rate tensor to numerically simulate the transonic compressor NASA Rotor 67 to evaluate the accuracy of turbulence modeling in numerical calculations of transonic compressors. The simulation results demonstrate that the four turbulence models are generally superior in the numerical computation of NASA Rotor 67, which essentially satisfies the requirements of the accuracy of engineering calculations; by comparing and analyzing the ability of the four turbulence models to predict the aerodynamic performance of transonic compressors and to capture the details of the flow inside the rotor. The errors of the Rotor 67 clogging flow rate calculated by the SA, SST, k-ɛ, and PAFV turbulence models with the experimental data are 0.9%, 0.8%, 0.7%, and 0.6%, respectively. The errors of the calculated peak efficiencies are 2.2%, 1.6%, 0.9%, and 4.9%. The SA and SST turbulence models were developed for the computational characteristics of the aerospace industry. Their computational stability is better and their outputs for Rotor 67 are comparable. The k-ɛ turbulence model calculates the pressure ratio and efficiency that are closest to the experimental data, but the computation of its details of the flow field near the wall surface is not ideal because the k-ɛ turbulence model cannot accurately capture the flow characteristics of the region of high shear stresses. The PAFV turbulence model has a better prediction of complex phenomena such as rotor internal shock wave location, shock–boundary layer interaction, etc., due to the use of a turbulent velocity scale in vector form, but the calculated rotor efficiency is small.","PeriodicalId":50845,"journal":{"name":"Aerospace America","volume":"6 1","pages":""},"PeriodicalIF":0.1,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90360075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Power Balance Strategies in Steady-State Simulation of the Micro Gas Turbine Engine by Component-Coupled 3D CFD Method 基于部件耦合三维CFD方法的微型燃气涡轮发动机稳态仿真功率平衡策略
IF 0.1 4区 工程技术
Aerospace America Pub Date : 2023-09-04 DOI: 10.3390/aerospace10090782
Yibing Xu, Lei Gao, Ruizhe Cao, Chong Yan, Ying Piao
{"title":"Power Balance Strategies in Steady-State Simulation of the Micro Gas Turbine Engine by Component-Coupled 3D CFD Method","authors":"Yibing Xu, Lei Gao, Ruizhe Cao, Chong Yan, Ying Piao","doi":"10.3390/aerospace10090782","DOIUrl":"https://doi.org/10.3390/aerospace10090782","url":null,"abstract":"Currently, an increasing number of designers have begun to pay attention to a new paradigm for evaluating the performance with full engine 3-dimensional computational fluid dynamics (3D CFD) simulations. Compared with the traditional component-based performance simulation method component-based performance simulation method (‘component-matched’ method), this novel ‘component-coupled’ method can evaluate the overall performance of the engine more physically and obtain more detailed flow field parameters simultaneously. Importantly, the power balance iteration should be introduced to the novel method to satisfy the constraints of the coaxial components for the gas turbine engine at steady state. By carrying out the ‘component-matched’ simulation and the ‘component-coupled’ simulation for a micro turbojet engine, the necessity of introducing the power balance iteration was discussed in this paper. The influence of steady-state co-working constraints on the engine performance was analysed and strategies for power balance iteration were proposed. To verify the capability and feasibility of this method, not only the co-working state but also the windmill state of the gas turbine engine were simulated by using the 3D CFD method considering power balance iteration. The results show that the power balance strategy proposed in this paper can converge the aerodynamic parameters as well as the power residual in a robust way.","PeriodicalId":50845,"journal":{"name":"Aerospace America","volume":"84 2 1","pages":""},"PeriodicalIF":0.1,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76114626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
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