System Approach to Finding Hydrodynamic Resistance Coefficient of a Nasal Cavity

Abstract

The purpose of the paper is the development of system approach to finding hydrodynamic resistance coefficient of nasal cavity, which takes into account the regimes of flow through nasal cavity and also specific anatomico-physiological features of a person's nasal cavity. The physics of the phenomenon causing formation of airflow in a nasal cavity at breathing is considered. The actuality of theoretical and practical researches of flow regime is shown. The analysis of existing methods of nasal breathin g assessment is carried out. The new methodology of receiving hydrodynamic resistance coefficient of a nasal cavity, differing from existing by lack of dimension is offered. The dimensionless coefficient of hydrodynamic resistance doesn't depend on individual geometric sizes o f a person's nasal cavity. It takes into account laminar, transition and turbulent regimes of flow. The classification of unilateral nasal obstruction independently from race differences of patients was obtained. Calculations of critical airflow rate and critical Reynolds number are proposed. Value of critical airflow rate allows splitting breathing cycle on 6 phases with identification of automodel zone. The 6-Phase Rhinomanometry is an extension of a 4-Phase Rhinomanometry. The separation on phases happens considering the structure of airflow that is directly connected with the performance of physiological functions. It allows investigation physiology of nasal breathing. Automodel zone of turbulent regime of flow as a marker of norm breathing will be investigated in further works. Also, future research will be connected with assessing a work of nose for different regimes of exploitation: calm breathing, breathing during physical exertion, investigation of nasal cycles.