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341.
The focus of the present research is performance enhancement of a vertical axis Darrieus‐type wind turbine using flow control techniques. The academic and industrial interest in vertical‐axis wind turbines (VAWTs) is increasing because of its suitability to urban areas, characterized by high turbulence and low wind speeds. The paper describes experimental work performed on a GOE222 asymmetrical airfoil intended to be used in a straight‐bladed Darrieus VAWT. Airfoil characteristics were measured in a wide range of incidence angles and Reynolds numbers, relevant for the operation of a small to medium size wind turbine. A variety of passive flow control (passive porosity and surface roughness) and active flow control techniques (boundary layer suction, pulsed suction) were tested in order to evaluate their effects on the airfoil performance. The measured effects of flow control on the 2D airfoil are integrated into a modified version of a double‐multiple streamtube model in order to predict the effects on the performance and efficiency of the turbine. It was found that the improvement of 2D airfoil characteristics can be translated into improvement of total turbine performance. By the use of active flow control, it was possible to increase the VAWT maximum mechanical output. When active flow control is properly activated taking into account the azimuth and Reynolds number conditioning, the effects could be greatly increased while consuming less energy, increasing the net efficiency of the entire system. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
342.
The paper presents a design concept for a control fin usually used in airborne vehicles such as UAV’s, Micro UAV’s and missiles. The research presents the design of a smart fin with integral piezoelectric actuators embedded in the airfoil skin. Electric field applied to the actuators would twist the airfoil leading to a change of the angle of attack. The study presents, analyze and demonstrates various lamination and actuation methods including a parametric performance investigation by finite elements models and closed form analytical model. The design and the theoretical results are verified by a manufactured smart wing demonstrator subjected to series of static and dynamic lab tests. 相似文献
343.
Dr. Arathy Jose Dr. Daniel Guest Dr. Remi LeGay Dr. Graham J. Tizzard Prof. Simon J. Coles Dr. Mariliza Derveni Dr. Edward Wright Dr. Lester Marrison Alpha A. Lee Aaron Morris Matt Robinson Prof. Frank von Delft Daren Fearon Dr. Lizbé Koekemoer Dr. Tetiana Matviuk Anthony Aimon Prof. Christopher J. Schofield Tika R. Malla Prof. Nir London Dr. Barnaby W. Greenland Prof. Mark C. Bagley Prof. John Spencer The Covid Moonshot Consortium 《ChemMedChem》2022,17(7):e202100641
The pentafluorosulfanyl (-SF5) functional group is of increasing interest as a bioisostere in medicinal chemistry. A library of SF5-containing compounds, including amide, isoxazole, and oxindole derivatives, was synthesised using a range of solution-based and solventless methods, including microwave and ball-mill techniques. The library was tested against targets including human dihydroorotate dehydrogenase (HDHODH). A subsequent focused approach led to synthesis of analogues of the clinically used disease modifying anti-rheumatic drugs (DMARDs), Teriflunomide and Leflunomide, considered for potential COVID-19 use, where SF5 bioisostere deployment led to improved inhibition of HDHODH compared with the parent drugs. The results demonstrate the utility of the SF5 group in medicinal chemistry. 相似文献
344.
Robert J. Slezaka Nir Keren Stephen B. Gilbert Matthew E. Harvey Saxon J. Ryan Alex J. Wiley 《Journal of Computer Assisted Learning》2023,39(1):113-124
Industrial systems can be complex and not intuitive to perceive. Therefore, students in technology and engineering programs can benefit from developing mental models of industrial systems during their journey in college. However, more often than not, these students do not have access to industrial facilities; thus, developing mental models for systems is a challenge. This paper examines the merit of an Immersive Virtual Reality (IVR) framework application in creating proper mental models for industrial systems in technology and engineering students. Two IVR applications were developed. One IVR application afforded interaction with components of a prefabricated industrial cooling water system (CWVR). In the other application, students designed and built industrial systems with IVR (system designer VR [SDVR]). SDVR facilitated constructive-generative engagement. A group of 33 students was divided into two; one group (the Design, experimental group) was tasked with building a system with SDVR and interacting with the cooling water system in CWVR. The other group was tasked with directly interacting with the CWVR without building a system with SDVR (the Interaction, comparison group). Students' mental models of the cooling water system in CWVR were evaluated following completing the interaction experience with CWVR. The results demonstrate that the causal model notion of the mental model of the cooling water system was significantly higher in the Design, experimental group. The results suggest that designing a rich IVR application that facilitates constructive-generative engagements may carry merit in informing student mental models of complex technical concepts. 相似文献