Mohammed Almijalli¹, Ravish Javed^1,, Abdulrahman Aldokhi¹, Fares Mohammed Alsuliman¹, Kareem Adnan Alharbi¹, Omar Altwijri¹

Children have special requirements in pulmonary drug delivery, as their lungs evolve continuously until they become adult. To deliver the drug to a specific area in the appropriate quantity, we need to study the deposition of particles. In our study we modelled and simulated airflow on a 5-year-old child using a CAD software to understand aerosol deposition. To design and simply the model of a child URT (Upper Respiratory Tract) on a CAD (Computer Aided Design) Software. Child specific model consist of mouth, trachea, and bronchi (left & right) with 11, 9, and 6.2 years old, respectively, was adopted. Using SolidWorks the URT model was sketched and extruded. All the simulation works were performed using software ANSYS CFX. An aerosol deposition converges at a steady-state condition for 500 iterations. A decrease in discharge was recorded as deposition transits from contraction prior to trachea at a velocity of 15 mm/s and a count of approximation of 28,000 with a time-lapse of 5 seconds. Therefore, the pressure and velocity of the particulate increases due to the contraction. Formulation particulate maximum velocity was recorded at 0.26 mm/s. Our findings suggest that a five-year-old URT model of a child has more aerosol depositions in comparison to adults and aerosol size range will evolve with age. In addition, deposition increase directly proportional to flow rate and with particle diameter.

aerosol deposition, 5-year-old child, upper respiratory tract, computational modelling