Discrete multi-physics simulations of diffusive and convective mass transfer in boundary layers containing motile cilia in lungs

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Colleges, School and Institutes

External organisations

  • Department of Mechanical and Manufacturing Engineering, University of Cyprus
  • Department of Health Science, Luleå University of Technology,


In this paper, the mass transfer coefficient (permeability) of boundary layers containing motile cilia is investigated by means of discrete multi-physics. The idea is to understand the main mechanisms of mass transport occurring in a ciliated-layer; one specific application being inhaled drugs in the respiratory epithelium. The effect of drug diffusivity, cilia beat frequency and cilia flexibility is studied. Our results show the existence of three mass transfer regimes. A low frequency regime, which we called shielding regime, where the presence of the cilia hinders mass transport; an intermediate frequency regime, which we have called diffusive regime, where diffusion is the controlling mechanism; and a high frequency regime, which we have called convective regime, where the degree of bending of the cilia seems to be the most important factor controlling mass transfer in the ciliated-layer. Since the flexibility of the cilia and the frequency of the beat changes with age and health conditions, the knowledge of these three regimes allows prediction of how mass transfer varies with these factors.


Original languageEnglish
Pages (from-to)34-42
Number of pages9
JournalComputers in Biology and Medicine
Early online date1 Feb 2018
Publication statusPublished - 1 Apr 2018


  • Cilia, Diffusivity, Discrete multi-physics, Mass transfer, Mass-spring model, Smoothed particle hydrodynamics