Construction of a hybrid lung model by combining a real geometry of the upper airways and an idealized geometry of the lower airways.

Background And Objective: Health care costs represent a substantial an increasing percentage of global expenditures. One key component is treatment of respiratory diseases, which account for one in twelve deaths in Europe. Computational simulations of lung airflow have potential to provide considerable cost reduction and improved outcomes.

In silico prototype of a human lung with a single airway to predict particle deposition.

Background: Experimental analyses of the flow of drug particles inside the human lung usually require that the patient be exposed to radiation and also of expensive equipment that often lack of enough accuracy. Numerical calculations based on CFD (computational fluid dynamics) have been proven to be a valuable tool to analyze flows in diverse applications.

Methods: The complexity of the human lung disallows running calculations on complete lung models due to the large number of cells that would be required.

Implementation of a specific boundary condition for a simplified symmetric single-path CFD lung model with OpenFOAM.

CFD modeling research about the lung airflow with a complete resolution and an adequate accuracy at all scales requires a great amount of computational resources due to the vast number of necessary grid elements. As a result, a common practice is to conduct simplifications that allows to manage it with ordinary computational power. In this study, the implementation of a special boundary condition in order to develop a simplified single conductive lung airway model, which exactly represents the effect of the removed airways, is presented.

Computational simulation of aqueous humour dynamics in the presence of a posterior-chamber versus iris-fixed phakic intraocular lens.

Purpose: To compare aqueous humour (AH) dynamics in the presence of a precrystalline (Implantable Collamer Lens®; ICL) or iris-fixed (Artiflex®) phakic intraocular lens (PIOL).

Methods: By computational fluid dynamics simulation, AH flow was modelled through a peripheral iridotomy (PI) or central lens hole (both 360 μm) in the presence of an Artiflex or ICL lens, respectively. The impacts of AH flow were then determined in terms of wall shear stress (WSS) produced on the endothelium or crystalline lens.