{"title":"Free-motion wind tunnel testing using a three-degree-of-freedom magnetic suspension system","authors":"Kazuyuki Ueno, Takushi Sato, Yuki Takeda, Reo Nagasaka, Mamoru Kikuchi","doi":"10.1007/s00348-024-03839-4","DOIUrl":null,"url":null,"abstract":"<p>A magnetic suspension system is developed for free-motion wind tunnel testing. An external magnet-yoke open magnetic circuit produces a levitation force acting on the disk magnet in the model, and stable suspension of the model is achieved by PID feedback control using two coils. The suspended models are free from support interference and move in three degrees of freedom in the wind tunnel. The pitch rotation around the <i>y</i>-axis and the translational motion in the <i>xz</i> plane under the influence of unsteady aerodynamic forces are observed using the motion capture technique. Parameter identification methods using Fourier analysis of the motion capture data are developed to determine the moment slope <span>\\(C_{\\textrm{M}\\alpha }\\)</span>, lift slope <span>\\(C_{\\textrm{L}\\alpha }\\)</span> and drag coefficient <span>\\(C_{\\textrm{D}}\\)</span>. The standard deviations of the identified values of <span>\\(C_{\\textrm{M}\\alpha }\\)</span>, <span>\\(C_{\\textrm{L}\\alpha }\\)</span> and <span>\\(C_{\\textrm{D}}\\)</span> are less than 5%, 8% and 6% of the respective means.</p>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"65 7","pages":""},"PeriodicalIF":2.3000,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Experiments in Fluids","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s00348-024-03839-4","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, MECHANICAL","Score":null,"Total":0}
引用次数: 0
Abstract
A magnetic suspension system is developed for free-motion wind tunnel testing. An external magnet-yoke open magnetic circuit produces a levitation force acting on the disk magnet in the model, and stable suspension of the model is achieved by PID feedback control using two coils. The suspended models are free from support interference and move in three degrees of freedom in the wind tunnel. The pitch rotation around the y-axis and the translational motion in the xz plane under the influence of unsteady aerodynamic forces are observed using the motion capture technique. Parameter identification methods using Fourier analysis of the motion capture data are developed to determine the moment slope \(C_{\textrm{M}\alpha }\), lift slope \(C_{\textrm{L}\alpha }\) and drag coefficient \(C_{\textrm{D}}\). The standard deviations of the identified values of \(C_{\textrm{M}\alpha }\), \(C_{\textrm{L}\alpha }\) and \(C_{\textrm{D}}\) are less than 5%, 8% and 6% of the respective means.
期刊介绍:
Experiments in Fluids examines the advancement, extension, and improvement of new techniques of flow measurement. The journal also publishes contributions that employ existing experimental techniques to gain an understanding of the underlying flow physics in the areas of turbulence, aerodynamics, hydrodynamics, convective heat transfer, combustion, turbomachinery, multi-phase flows, and chemical, biological and geological flows. In addition, readers will find papers that report on investigations combining experimental and analytical/numerical approaches.