Consideration of the respiratory cycle asymmetry in the numerical modeling of the submicron particles deposition in the human nasal cavity

Abstract

Abstract.A detailed study of the behavior of the U-shaped curve was conducted, which described deposition efficiency of inhaled particles in human nasal cavity. The particles in the range from 1 nm to 20 μm are considered. Calculations of air flow and particles deposition were carried out for symmetrical (idealized) and asymmetrical (real) breathing cycles at the same volume of inhaled air, which corresponded to calm breathing. The calculations were performed on the base of the mathematical model of the nasal cavity of healthy person using software package ANSYS (FLUENT 12). The comparison of the results was made between these calculations, and also with the results obtained at quasi-stationary statement of the problem for several values of flow rate. The comparison of the results of quasi-stationary calculations with available calculated and experimental data (in vivo in vitro) was fulfilled previously. Good agreement of the results was obtained. It is shown that the real distribution of deposition efficiency as a function of the particle size can be obtained via a certain combination of the results of quasi-stationary calculations, without the use of laborious and timeconsuming non-stationary calculation.