{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T23:09:47Z","timestamp":1771456187078,"version":"3.50.1"},"reference-count":47,"publisher":"The Company of Biologists","issue":"14","license":[{"start":{"date-parts":[[2021,7,15]],"date-time":"2021-07-15T00:00:00Z","timestamp":1626307200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/www.biologists.com\/user-licence-1-1\/"}],"funder":[{"name":"National Science Foundation","award":["1351322"],"award-info":[{"award-number":["1351322"]}]},{"name":"National Science Foundation","award":["2027523"],"award-info":[{"award-number":["2027523"]}]},{"DOI":"10.13039\/100000185","name":"Defense Advanced Research Projects Agency","doi-asserted-by":"crossref","award":["W911NF1010040"],"award-info":[{"award-number":["W911NF1010040"]}],"id":[{"id":"10.13039\/100000185","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2021,7,15]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n               <jats:p>Flying snakes flatten their body to form a roughly triangular cross-sectional shape, enabling lift production and horizontal acceleration. While gliding, they also assume an S-shaped posture, which could promote aerodynamic interactions between the fore and the aft body. Such interactions have been studied experimentally; however, very coarse models of the snake's cross-sectional shape were used, and the effects were measured only for the downstream model. In this study, the aerodynamic interactions resulting from the snake's posture were approximated using two-dimensional anatomically accurate airfoils positioned in tandem to mimic the snake's geometry during flight. Load cells were used to measure the lift and drag forces, and flow field data were obtained using digital particle image velocimetry (DPIV). The results showed a strong dependence of the aerodynamic performance on the tandem arrangement, with the lift coefficients being generally more influenced than the drag coefficients. Flow field data revealed that the tandem arrangement modified the separated flow and the wake size, and enhanced the lift in cases in which the wake vortices formed closer to the models, producing suction on the dorsal surface. The downforce created by the flow separation from the ventral surface of the models at 0\u00a0deg angle of attack was another significant factor contributing to lift production. A number of cases showing large variations of aerodynamic performance included configurations close to the most probable posture of airborne flying snakes, suggesting that small postural variations could be used to control the glide trajectory.<\/jats:p>","DOI":"10.1242\/jeb.233635","type":"journal-article","created":{"date-parts":[[2021,6,7]],"date-time":"2021-06-07T12:13:15Z","timestamp":1623067995000},"source":"Crossref","is-referenced-by-count":11,"title":["The aerodynamics of flying snake airfoils in tandem configuration"],"prefix":"10.1242","volume":"224","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3252-5111","authenticated-orcid":false,"given":"Farid","family":"Jafari","sequence":"first","affiliation":[{"name":"School of Engineering , Grand Valley State University, Grand Rapids, MI 49504, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel","family":"Holden","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA 24060, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roderick","family":"LaFoy","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA 24060, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pavlos P.","family":"Vlachos","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Purdue University, West Lafayette, IN 47906, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4465-1097","authenticated-orcid":false,"given":"John J.","family":"Socha","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"237","published-online":{"date-parts":[[2021,7,23]]},"reference":[{"key":"2021072615290161700_JEB233635C1","doi-asserted-by":"publisher","first-page":"155","DOI":"10.1007\/s00162-007-0045-2","article-title":"Hydrodynamics of a biologically inspired tandem flapping foil configuration","volume":"21","author":"Akhtar","year":"2007","journal-title":"Theor. 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MSc thesis, Virginia Tech, VA, USA."},{"key":"2021072615290161700_JEB233635C13","doi-asserted-by":"publisher","first-page":"382","DOI":"10.1242\/jeb.090902","article-title":"Aerodynamics of the flying snake Chrysopelea paradisi: how a bluff body cross-sectional shape contributes to gliding performance","volume":"217","author":"Holden","year":"2014","journal-title":"J. Exp. Biol."},{"key":"2021072615290161700_JEB233635C14","doi-asserted-by":"publisher","first-page":"195","DOI":"10.7227\/IJMEE.33.3.2","article-title":"Two-dimensional analysis of tandem\/staggered airfoils using computational fluid dynamics","volume":"33","author":"Husain","year":"2005","journal-title":"Int. J. Mech. Eng. 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