2026-10-14T21:16:49Z https://api.figshare.com/v2/oai

oai:figshare.com:article/34035939 2026-09-30T17:42:31Z category_1 category_915 category_21 category_272 category_39 category_734 category_106 portal_5 item_type_6 month_year_09_2026

<p>Wake vortices shown as iso surfaces of total vorticity [s⁻¹] (iso value = 150), colored by downwash velocity of a sample sequence of a European nightjar flying at 2.6 m/s.</p> L. Christoffer Johansson (8029388) Gabriel Norevik (589846) Sonja Friman (25145400) Anders Hedenström (150704) Biophysics Physical Sciences not elsewhere classified Biotechnology Environmental Sciences not elsewhere classified Ecology Biological Sciences not elsewhere classified Science Policy using wake visualization reduced span efficiency phenomenon may stem multiple costly behaviors may apply generally kinematic analysis suggests characteristic previously attributed caprimulgus europaeus </ cruising speed efficiency reflects complex tradeoffs european nightjar (< also uses slow div >< p cruising flight — cruising speeds tradeoffs seen slow flight nightjar ’ hummingbirds — wing shape wing folding wind tunnel results highlight particularly interesting makes studies generating lift flight speeds flight performance flapping flight feeding ecology faster speeds existing paradigm ecological demands distance migrant animals engaged aerodynamic mechanisms aerodynamic measurements <p>Note the complex wake during the “upstroke” (lower inlet), cutting through two successive downstrokes and one upstroke and the weak flow in the body region during the downstroke (upper inlet). The inlets show in-plane velocity vectors on a background showing the streamwise vorticity with blue showing clockwise rotation and yellow/red counterclockwise rotation. Vectors are not scaled the same in inlets but are scaled to facilitate interpretation of the flow. Axes units are in m.</p> <p>(PDF)</p> 2026-09-30T18:03:55Z Text Journal contribution 10.1371/journal.pbio.3004023.s003 https://figshare.com/articles/journal_contribution/_p_Wake_vortices_shown_as_iso_surfaces_of_total_vorticity_s_sup_1_sup_iso_value_150_colored_by_downwash_velocity_of_a_sample_sequence_of_a_European_nightjar_flying_at_2_6_m_s_p_/34035939 CC BY 4.0