The Aerodynamic Filtering System of the Sandfish Lizard
Sprache des Vortragstitels:
Englisch
Original Tagungtitel:
Bionik-Kongress 2018
Sprache des Tagungstitel:
Deutsch
Original Kurzfassung:
The sandfish lizard Scincus scincus spends almost its entire life buried in aeolian sand. To
prevent sand grains from entering its lungs, it was hypothesized [1] that particles are aerodynamically
filtered when they enter the nasal cavity: The vestibulum is a narrow rounded channel
leading to a kind of »chamber«, where cilia and mucus are present. In this chamber the particles
get caught by mucus during a slow, long-lasting inhalation (2 s), and eventually get exhaled because
of an intense, cough-like exhalation that lasts only 45 ms. To verify this theory we studied
the filtering system by computational fluid dynamic simulations of fluid and particle flow. The
results show that during inhalation the flow profile anterior to and in the chamber is characterized
by strong cross-flow velocities that move the sand grains towards the mucus-covered wall;
during the intense exhalation particles of all size are coughed out. In this context we explore
the possibility to optimize state-of-the-art filtering systems.