Numerical Simulation of Airflow in a Respiratory Muscle Strength Evaluation Device
AbstractMeasurement of Respiratory Muscle Strength (RMS) allows identifying malfunctions and muscular abnormalities in lung function. It can be evaluated from static measures through Maximum Inspiratory and Expiratory Pressures or inferred by dynamic maneuvers through Maximum Voluntary Ventilation. The aim of this work was to perform a computational evaluation of the maximal respiratory pressures in a concept device for the dynamic evaluation of respiratory muscle strength, in different respiratory loads. The tubular domain of the numerical simulation was approximated to an orifice plate, admitting a mass flow profile at the inlet and a condition of opening to the environment at the outlet. Seven different openings were evaluated at the exit of the domain and, for each of them, the pressure profile was drawn at the entrance of the device. Thus, a curve was obtained relating aperture and maximum inspiratory pressure and expiration reached.