Estimate of Strouhal and Reynolds numbers for swimming penguins

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F21%3A10436022" target="_blank" >RIV/00216208:11320/21:10436022 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=DhPYhkQpSa" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=DhPYhkQpSa</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1111/jav.02886" target="_blank" >10.1111/jav.02886</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Estimate of Strouhal and Reynolds numbers for swimming penguins

Popis výsledku v původním jazyce

Propulsion performance of swimming and flying animals is often evaluated by using dimensionless numbers, such as the Strouhal and Reynolds numbers. They have been shown to allow a better understanding of locomotion efficiency, using relatively simple approaches and avoiding overly complex computational models. Specifically, it has been reported that efficient propulsion is more likely to occur when Strouhal number values - estimated from propulsive frequencies and amplitudes - are within a relatively narrow range, depending on the corresponding Reynolds number, broadly expressing the fluid resistance to the animal motion. We have estimated both Strouhal and Reynolds numbers for seven species of penguins after analysing relevant kinematic data taken from the literature. The obtained values neatly indicate that, as expected, penguins employ efficient propulsion mechanisms. Additionally, by comparing these values with those for alcids - seabirds that can also fly - we have found that penguins swim at least as efficiently as alcids. However, we have also found that the swimming number - proportional to the product of Strouhal and Reynolds numbers - neatly correlates to the diving abilities of the considered species and apparently indicates, in a straightforward hierarchical manner, the gains in diving due to the loss of flying abilities. Within the penguin species, a clear correlation is also observed between diving performance and drag coefficient values.

Název v anglickém jazyce

Estimate of Strouhal and Reynolds numbers for swimming penguins

Popis výsledku anglicky

Propulsion performance of swimming and flying animals is often evaluated by using dimensionless numbers, such as the Strouhal and Reynolds numbers. They have been shown to allow a better understanding of locomotion efficiency, using relatively simple approaches and avoiding overly complex computational models. Specifically, it has been reported that efficient propulsion is more likely to occur when Strouhal number values - estimated from propulsive frequencies and amplitudes - are within a relatively narrow range, depending on the corresponding Reynolds number, broadly expressing the fluid resistance to the animal motion. We have estimated both Strouhal and Reynolds numbers for seven species of penguins after analysing relevant kinematic data taken from the literature. The obtained values neatly indicate that, as expected, penguins employ efficient propulsion mechanisms. Additionally, by comparing these values with those for alcids - seabirds that can also fly - we have found that penguins swim at least as efficiently as alcids. However, we have also found that the swimming number - proportional to the product of Strouhal and Reynolds numbers - neatly correlates to the diving abilities of the considered species and apparently indicates, in a straightforward hierarchical manner, the gains in diving due to the loss of flying abilities. Within the penguin species, a clear correlation is also observed between diving performance and drag coefficient values.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10613 - Zoology

Projekt

<a href="/cs/project/GA19-00939S" target="_blank" >GA19-00939S: Dynamika velkých vírů v kvantové turbulenci</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Avian Biology

ISSN

0908-8857

e-ISSN

—

Svazek periodika

2021

Číslo periodika v rámci svazku

2021

Stát vydavatele periodika

DK - Dánské království

Počet stran výsledku

6

Strana od-do

e02886

Kód UT WoS článku

000730466000001

EID výsledku v databázi Scopus

2-s2.0-85121370243