The vertical axis wind turbine (VAWT) configuration has many advantages for an offshore wind turbine installation. The VAWT is omnidirectional and its rotating mechanical components can be placed close to sea level. In this paper, the three dimensional (3D) computational fluid dynamics analysis of a large-scale 5 MW VAWT is conducted. At the optimum tip-speed ratio (TSR), the VAWT maximum inline force was 75% larger than the maximum lateral force.
{"title":"Three-Dimensional Computational Fluid Dynamic Analysis of a Large-Scale Vertical Axis Wind Turbine","authors":"H. Brian","doi":"10.36959/422/454","DOIUrl":"https://doi.org/10.36959/422/454","url":null,"abstract":"The vertical axis wind turbine (VAWT) configuration has many advantages for an offshore wind turbine installation. The VAWT is omnidirectional and its rotating mechanical components can be placed close to sea level. In this paper, the three dimensional (3D) computational fluid dynamics analysis of a large-scale 5 MW VAWT is conducted. At the optimum tip-speed ratio (TSR), the VAWT maximum inline force was 75% larger than the maximum lateral force.","PeriodicalId":130516,"journal":{"name":"Journal of Aerospace Engineering and Mechanics","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131807610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The today’s efforts of aerospace system engineers, not to mention human psychologists, to assure adequate operational reliability of electronic-and-photonic (E&P) products and satisfactory success-and-safety of a mission or of an extraordinary situation, are, as a rule, based on more or less trustworthy statistics and on what is known as best practices. These efforts are typically unquantifiable, i.e. do not end up with numerical data that enable comparing different possible scenarios of the outcome of a planned undertaking. The objective of this review is to show, using examples from different and sometimes even unconnected areas of aerospace E&P and ergonomics engineering, how probabilistic predictive modeling (PPM) geared to a carefully designed, thoroughly conducted and adequately interpreted highly-focused and highly cost effective failure-oriented accelerated testing (FOAT) can be employed to quantify what is typically considered as “unquantifiable”, i.e., to evaluate the lifetime and the corresponding probability of failure (PoF) of an aerospace E&P system, and/or the role of the human factor (HF), and to predict the outcome of a human-in-the-loop (HITL) related mission or an extraordinary situation, when equipment’s reliability (both hard- and software) and human performance contribute jointly to the never-zero PoF of a mission or an extraordinary situation. The reader is not expected to necessarily “connect the dots”, associated with different situations and examples provided. The only, but an important, feature that these examples have in common is that many aerospace system and ergonomics engineering related tasks and problems, which are perceived and treated today as unquantifiable, could and, in the author’s opinion, should be quantified to assure safe and successful outcome of a particular aerospace undertaking of importance.
{"title":"\"Quantifying the Unquantifiable\" in Aerospace Electronics and Ergonomics Engineering: Review","authors":"S. E","doi":"10.36959/422/449","DOIUrl":"https://doi.org/10.36959/422/449","url":null,"abstract":"The today’s efforts of aerospace system engineers, not to mention human psychologists, to assure adequate operational reliability of electronic-and-photonic (E&P) products and satisfactory success-and-safety of a mission or of an extraordinary situation, are, as a rule, based on more or less trustworthy statistics and on what is known as best practices. These efforts are typically unquantifiable, i.e. do not end up with numerical data that enable comparing different possible scenarios of the outcome of a planned undertaking. The objective of this review is to show, using examples from different and sometimes even unconnected areas of aerospace E&P and ergonomics engineering, how probabilistic predictive modeling (PPM) geared to a carefully designed, thoroughly conducted and adequately interpreted highly-focused and highly cost effective failure-oriented accelerated testing (FOAT) can be employed to quantify what is typically considered as “unquantifiable”, i.e., to evaluate the lifetime and the corresponding probability of failure (PoF) of an aerospace E&P system, and/or the role of the human factor (HF), and to predict the outcome of a human-in-the-loop (HITL) related mission or an extraordinary situation, when equipment’s reliability (both hard- and software) and human performance contribute jointly to the never-zero PoF of a mission or an extraordinary situation. The reader is not expected to necessarily “connect the dots”, associated with different situations and examples provided. The only, but an important, feature that these examples have in common is that many aerospace system and ergonomics engineering related tasks and problems, which are perceived and treated today as unquantifiable, could and, in the author’s opinion, should be quantified to assure safe and successful outcome of a particular aerospace undertaking of importance.","PeriodicalId":130516,"journal":{"name":"Journal of Aerospace Engineering and Mechanics","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132335236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Wild, J. Murray, Ayiei Ayiei, M. Eqbal, Eranga Batuwangala
The survey was conducted at RMIT University open day, on a Sunday when the campus was open to the public. It should be noted that the survey was conducted on the street, and the campus is in fact 6% of the Melbourne central business district. As such, participation was open to the general public, with diverse demographics collected. One hundred paper surveys were distributed and collected, of which 83 were completed correctly. Mistakes were made, some with multiple options selected etc; these responses were omitted.
{"title":"Public Perception of Drones… or Should that be Remotely Piloted Aircraft Systems?","authors":"G. Wild, J. Murray, Ayiei Ayiei, M. Eqbal, Eranga Batuwangala","doi":"10.36959/422/438","DOIUrl":"https://doi.org/10.36959/422/438","url":null,"abstract":"The survey was conducted at RMIT University open day, on a Sunday when the campus was open to the public. It should be noted that the survey was conducted on the street, and the campus is in fact 6% of the Melbourne central business district. As such, participation was open to the general public, with diverse demographics collected. One hundred paper surveys were distributed and collected, of which 83 were completed correctly. Mistakes were made, some with multiple options selected etc; these responses were omitted.","PeriodicalId":130516,"journal":{"name":"Journal of Aerospace Engineering and Mechanics","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116948121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The objective of the analysis is to demonstrate how the Boltzmann-Arrhenius-Zhurkov (BAZ) model, originally suggested by Zhurkov in the kinetic concept of the strength of solids as a generalization of the Arrhenius theory of chemical reactions, can be effectively employed for the prediction of the lifetime of electronic materials experiencing ionizing radiation. The “loading term” γσ in the original BAZ model, where σ is the tensile mechanical stress and γ is the sensitivity factor, is replaced with the term γRD, where D is the radiation level and γR is the sensitivity factor. Leakage current measured during the failure-oriented-accelerated-testing (FOAT) is considered in our analysis as a suitable indication/criterion of the level of the induced damage. FOAT terminates, when the agreed upon critical value of the leakage current is reached. Citation: Ponomarev A, Suhir E (2019) Predicted Useful Lifetime of Aerospace Electronics Experiencing Ionizing Radiation: Application of BAZ Model. J Aerosp Eng Mech 3(1):167-169 Ponomarev and Suhir. Dermatol Arch 2019, 3(1):167-169 Open Access | Page 168 | Here T is the testing temperature. In such a situation the factor γI does not affect the factor γR. Finally, after the sensitivity factors γI and γR are evaluated, the activation energy can be found as
{"title":"Predicted Useful Lifetime of Aerospace Electronics Experiencing Ionizing Radiation: Application of BAZ Model","authors":"A. Ponomarev, E. Suhir","doi":"10.36959/422/437","DOIUrl":"https://doi.org/10.36959/422/437","url":null,"abstract":"The objective of the analysis is to demonstrate how the Boltzmann-Arrhenius-Zhurkov (BAZ) model, originally suggested by Zhurkov in the kinetic concept of the strength of solids as a generalization of the Arrhenius theory of chemical reactions, can be effectively employed for the prediction of the lifetime of electronic materials experiencing ionizing radiation. The “loading term” γσ in the original BAZ model, where σ is the tensile mechanical stress and γ is the sensitivity factor, is replaced with the term γRD, where D is the radiation level and γR is the sensitivity factor. Leakage current measured during the failure-oriented-accelerated-testing (FOAT) is considered in our analysis as a suitable indication/criterion of the level of the induced damage. FOAT terminates, when the agreed upon critical value of the leakage current is reached. Citation: Ponomarev A, Suhir E (2019) Predicted Useful Lifetime of Aerospace Electronics Experiencing Ionizing Radiation: Application of BAZ Model. J Aerosp Eng Mech 3(1):167-169 Ponomarev and Suhir. Dermatol Arch 2019, 3(1):167-169 Open Access | Page 168 | Here T is the testing temperature. In such a situation the factor γI does not affect the factor γR. Finally, after the sensitivity factors γI and γR are evaluated, the activation energy can be found as","PeriodicalId":130516,"journal":{"name":"Journal of Aerospace Engineering and Mechanics","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123546926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
As part of the search for the next future airliner configuration, and to mitigate the negative impact of air travels on the environment, there have been renewed interests in the aircraft design of unconventional configurations such as the Blended Wing Body and Joined Wing aircraft concepts. The Joined/Box-Wing aircraft configuration attracted the attention of researchers due to its claimed merits of reduced structural weight and low induced drag.
{"title":"Review of Structural Issues in the Design of a Box Wing Aircraft","authors":"P. Jemitola, P. Okonkwo","doi":"10.36959/422/436","DOIUrl":"https://doi.org/10.36959/422/436","url":null,"abstract":"As part of the search for the next future airliner configuration, and to mitigate the negative impact of air travels on the environment, there have been renewed interests in the aircraft design of unconventional configurations such as the Blended Wing Body and Joined Wing aircraft concepts. The Joined/Box-Wing aircraft configuration attracted the attention of researchers due to its claimed merits of reduced structural weight and low induced drag.","PeriodicalId":130516,"journal":{"name":"Journal of Aerospace Engineering and Mechanics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116068341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aerodynamic Forces mainly lift and Drag acting on an aircraft, are directly related to the geometry and wing profile of an aircraft. In this research we first designed a blended wing UAV (using X48B as a baseline model) and then performed the CFD analysis. Focusing on the lift to drag ratio in Cruise conditions, we made changes to our initial design based on critical pressure regions found by simulation and afterwards improved our design to almost three times by making changes to the initial geometry.
{"title":"Design and CFD Analysis of a Blended Wing UAV (A Conceptual Design)","authors":"Khan Tayyab","doi":"10.36959/422/435","DOIUrl":"https://doi.org/10.36959/422/435","url":null,"abstract":"Aerodynamic Forces mainly lift and Drag acting on an aircraft, are directly related to the geometry and wing profile of an aircraft. In this research we first designed a blended wing UAV (using X48B as a baseline model) and then performed the CFD analysis. Focusing on the lift to drag ratio in Cruise conditions, we made changes to our initial design based on critical pressure regions found by simulation and afterwards improved our design to almost three times by making changes to the initial geometry.","PeriodicalId":130516,"journal":{"name":"Journal of Aerospace Engineering and Mechanics","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129832611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-06-06DOI: 10.21694/2572-2921.18001
Orlov Sa
The nature of light has been studied by scientists since the Renaissance. According to some scientists, light had a wave nature. Others defended the corpuscular theory of the origin of light. To the founders of the wave theory, in the first place, should be attributed Rene Descartes. He represented light as a disturbance in the world substance [1]. The founder of the corpuscular theory was Pierre Gassendi [2]. The same point of view was followed by Isaac Newton [3]. Later, the wave theory of light was investigated by Robert Hooke [4] and Christian Huygens [5]. Thomas Jung [6] in the early 19 th century, his experiments with diffraction received evidence for the recognition of the wave theory. In his opinion, different colors correspond to different wavelengths. In 1817 the wave theory of light was followed by Augustin Fresnel in 1817 [7]. When considering the problem of thermal equilibrium of an absolutely black body, Max Planck [8] formulated his idea of the emission of light by portions light quanta, which were called photons. Experiments of Malus and Bio [9] with polarization provided, as it seemed then, convincing evidence in favor of corpuscular theory and against the wave theory. In quantum mechanics, the idea of Dui de Broglie [10] about corpuscular-wave dualism was confirmed.
自文艺复兴以来，科学家们一直在研究光的本质。根据一些科学家的说法，光具有波动的性质。其他人则为光的起源的微粒理论辩护。首先，波动理论的创始人应该归功于勒内·笛卡尔。他把光描绘成世界物质中的扰动[1]。微粒理论的创始人是皮埃尔·加森迪[2]。艾萨克·牛顿(Isaac Newton)也持同样观点[3]。后来，Robert Hooke[4]和Christian Huygens[5]研究了光的波动理论。汤姆斯·荣格[6]在19世纪早期，他的衍射实验为波理论的认可提供了证据。在他看来，不同的颜色对应不同的波长。1817年，菲涅尔(Augustin Fresnel)提出了光的波动理论[7]。在考虑绝对黑体的热平衡问题时，马克斯·普朗克[8]提出了光由部分光量子发射的思想，这些光量子被称为光子。Malus和Bio[9]的极化实验提供了令人信服的证据，支持微粒理论，反对波动理论。在量子力学中，Dui de Broglie[10]关于粒子波二重性的思想得到了证实。
{"title":"Photon Mass","authors":"Orlov Sa","doi":"10.21694/2572-2921.18001","DOIUrl":"https://doi.org/10.21694/2572-2921.18001","url":null,"abstract":"The nature of light has been studied by scientists since the Renaissance. According to some scientists, light had a wave nature. Others defended the corpuscular theory of the origin of light. To the founders of the wave theory, in the first place, should be attributed Rene Descartes. He represented light as a disturbance in the world substance [1]. The founder of the corpuscular theory was Pierre Gassendi [2]. The same point of view was followed by Isaac Newton [3]. Later, the wave theory of light was investigated by Robert Hooke [4] and Christian Huygens [5]. Thomas Jung [6] in the early 19 th century, his experiments with diffraction received evidence for the recognition of the wave theory. In his opinion, different colors correspond to different wavelengths. In 1817 the wave theory of light was followed by Augustin Fresnel in 1817 [7]. When considering the problem of thermal equilibrium of an absolutely black body, Max Planck [8] formulated his idea of the emission of light by portions light quanta, which were called photons. Experiments of Malus and Bio [9] with polarization provided, as it seemed then, convincing evidence in favor of corpuscular theory and against the wave theory. In quantum mechanics, the idea of Dui de Broglie [10] about corpuscular-wave dualism was confirmed.","PeriodicalId":130516,"journal":{"name":"Journal of Aerospace Engineering and Mechanics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133157065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Cylindrical Panel Like Response of Fully Surface Parallel Restrained Simply Supported Hyperbolic Paraboloidal Thick General Cross-ply Panels","authors":"A. Reaz Chaudhuri, A. Sinan Oktem","doi":"10.36959/422/459","DOIUrl":"https://doi.org/10.36959/422/459","url":null,"abstract":"","PeriodicalId":130516,"journal":{"name":"Journal of Aerospace Engineering and Mechanics","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114211410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ariane Group is currently developing space vehicles using new LOx/LCH4 propulsion technology. Venting or draining out methane from the tanks in flight at various altitudes concerns the safety management. This paper is focusing on the modeling of liquid methane draining around a moving space plane. A cryogenic round jet in an air crossflow has to be considered. However, the computational cost for a vaporizing liquid jet model is too high with respect to the goals of the study. A more time-friendly densified gas model has thus been developed. Experiments on liquid nitrogen were conducted to validate the numerical results. Numerical and experimental jet trajectories are in the same order of magnitude. Liquid column height is also properly modeled. The model is thus validated for pre-study calculations where global behaviors need to be determined without a prohibitive cost.
{"title":"Numerical and Experimental Study of Liquid Cryogenic Jet around a Space Plane and Its Ignition Risk","authors":"Dougal J, G. P., W. M., A. T., Dutheil Jp, B. Y.","doi":"10.36959/422/458","DOIUrl":"https://doi.org/10.36959/422/458","url":null,"abstract":"Ariane Group is currently developing space vehicles using new LOx/LCH4 propulsion technology. Venting or draining out methane from the tanks in flight at various altitudes concerns the safety management. This paper is focusing on the modeling of liquid methane draining around a moving space plane. A cryogenic round jet in an air crossflow has to be considered. However, the computational cost for a vaporizing liquid jet model is too high with respect to the goals of the study. A more time-friendly densified gas model has thus been developed. Experiments on liquid nitrogen were conducted to validate the numerical results. Numerical and experimental jet trajectories are in the same order of magnitude. Liquid column height is also properly modeled. The model is thus validated for pre-study calculations where global behaviors need to be determined without a prohibitive cost.","PeriodicalId":130516,"journal":{"name":"Journal of Aerospace Engineering and Mechanics","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127750934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Predicted Low-Cycle-Fatigue Lifetime of Solder Joint Interconnections: Application of Hall's Approach and Boltzmann-Arrhenius-Zhurkov (Baz) Model","authors":"S. E","doi":"10.36959/422/460","DOIUrl":"https://doi.org/10.36959/422/460","url":null,"abstract":"","PeriodicalId":130516,"journal":{"name":"Journal of Aerospace Engineering and Mechanics","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129101803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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