Cough impact in the human trachea
In a two-way coupled Fluid-Structure-Interaction (FSI), the flow field and the structure interact with each other. The fluid-induced loading (pressure, wall shear stress) acts on the structure and leads to its displacement and deformation. The resulting displacement, in turn, influences the flow field.
| DOWNLOAD | high resolution AVI-video Fluid−Structure−Interaction in a human trachea model [compressed AVI-file 2,97 MB] 
A cough impact in the human trachea is one example for a two-way Fluid-Structure-Interaction. A cough impact results in a temporary highly increased air flow rate.
| The human trachea of an adult is about 12 cm long by about 2.5 cm in diameter. It is reinforced by C-shaped bands of cartilage in the trachea wall. The open portion of the C is spanned by the trachealis muscle. The trachea branches into the bronchi. | |||||
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Anatomy of the trachea (left) and the FE model for the numerical simulation includes all relevant trachea features (right).
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In a coupled CFD and FE analysis, the flow field inside the trachea as well as its resulting deformation and stress distribution can be estimated at any time and location. The temporary highly increased air flow rate inside the trachea leads to an increased pressure. The surrounding trachea walls are deformed due to the momentary acting pressure. The deformed trachea wall, in turn, influences the flow field. The deformation of the trachea muscle is greater than the cartilage deformation, owing to their different stiffness.
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Exemplary human cough impact (left) and simplified assumption for the numerical simulation (right).
Applying the coupled numerical simulation of fluid and structure mechanics it is possible to efficiently analyse, visualise and optimise these interactions.
| ASD offers coupled FSI simulations for any kind of medical or engineering application. Copyright © 1998, ASD Advanced Simulation & Design GmbH  , All rights reserved.last update: webmaster@asd-online.com | ||||