Simulation of sprayed particle deposition in a human nasal cavity including a nasal spray device

Inthavong, Kiao; Ge, Qinjiang; M.K., Camby; Yang, William; Tu, Jiyuan

doi:10.1016/j.jaerosci.2010.11.008

Cited by 91 publications

(41 citation statements)

References 24 publications

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“…A similar work to use such a high-resolution mesh is that of Doorly et al (2008). Earlier studies by the authors found that a mesh in excess of 2.0 million cells provided grid independence for the nasal cavity region (Inthavong et al, 2011a) among other studies (Golshahi et al, 2010;Lee et al, 2010;Moghadas et al, 2011), while a mesh of 1.2 million cells was sufficient for grid independence of the room with human occupant model (King Se et al, 2010). The visualization and generation of the mesh was possible on a PC computer with 32 Gb Ram, and 8 processor cores.…”

Section: Computational Geometrymentioning

confidence: 99%

Source and trajectories of inhaled particles from a surrounding environment and its deposition in the respiratory airway

Inthavong

Ge²,

Li³

et al. 2013

Inhalation Toxicology

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The inhalation exposure to airborne particles is investigated using a newly developed computational model that integrates the human respiratory airway with a human mannequin and at an enclosed room environment. Three free-stream air flow velocities (0.05, 0.20, and 0.35 m s⁻¹) that are in the range of occupational environments are used. Particles are released from different upstream locations and their trajectories are shown, which revealed that the trajectory paths of 80 μm particles that are inhaled are the same from the three different upstream planes evaluated. Smaller particles, 1 and 10 μm, exhibited different inhalation paths when released from different upstream distances. The free-stream velocity also has an effect on the particle trajectory particularly for larger particles. The aspiration efficiency for an extended range of particle sizes was evaluated. Reverse particle tracking matches the deposition in the respiratory airway with its initial particle source location. This can allow better risk assessments, and dosimetry determination due to inhalation exposure to contaminant sources.

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Section: Computational Geometrymentioning

confidence: 99%

Source and trajectories of inhaled particles from a surrounding environment and its deposition in the respiratory airway

Inthavong

Ge²,

Li³

et al. 2013

Inhalation Toxicology

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“…Computational simulation of particle deposition using validated airway casts or 3D airway models has been used to assess nasal drug delivery. 16,17 Using these simulations, the optimum method of delivery and its impact on the physical properties of the contrast agent, including radioopacity, could be identified.…”

Section: 13mentioning

confidence: 99%

Topical contrast agents to improve soft-tissue contrast in the upper airway using cone beam CT: a pilot study

Alsufyani

Noga²,

Finlay³

et al. 2013

Dentomaxillofacial Radiology

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The purpose of this study is to explore the topical use of radiographic contrast agents to enhance soft-tissue contrast on cone beam CT (CBCT) images. Different barium sulphate concentrations were first tested using an airway phantom. Different methods of barium sulphate application (nasal drops, syringe, spray and sinus wash) were then tested on four volunteers, and nebulized iodine was tested in one volunteer. CBCT images were performed and then assessed subjectively by two examiners for contrast agent uniformity and lack of streak artefact. 25.0% barium sulphate presented adequate viscosity and radiodensity. Barium sulphate administered via nasal drops and sprays showed non-uniform collection at the nostrils, along the inferior and/or middle nasal meatuses and posterior nasal choana. The syringe and sinus wash showed similar results with larger volumes collecting in the naso-oropharynx. Nebulized iodine failed to distribute into the nasal cavity and scarcely collected at the nostrils. All methods of nasal application failed to adequately reach or uniformly coat the nasal cavity beyond the inferior nasal meatuses. The key factors to consider for optimum topical radiographic contrast in the nasal airway are particle size, flow velocity and radio-opacity.

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“…The first numerical studies of the airflow pattern in the nasal airway were accomplished by Keyhani et al [20] and Subramaniam et al [21]. Recently, particle dispersion and deposition have been studied in realistic nasal airways [22,23,24]. These simulations were performed with the commercial software packages CFX [22] and Fluent [23,24].…”

Section: Introductionmentioning

confidence: 99%

“…Recently, particle dispersion and deposition have been studied in realistic nasal airways [22,23,24]. These simulations were performed with the commercial software packages CFX [22] and Fluent [23,24]. Most of the research in this area considers a steady inlet airflow [25] or an unsteady flow representing inhalation-exhalation cycles [26].…”

Section: Introductionmentioning

confidence: 99%

Numerical Simulation of the Dispersion and Deposition of a Spray Carried by a Pulsating Airflow in a Patient-Specific Human Nasal Cavity

Farnoud

Cui

Baumann

et al. 2017

Proceedings ILASS–Europe 2017. 28th Conference on Liquid Atomization and Spray Systems

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The present numerical study concerns the dispersion and deposition of a nasal spray in a patient-specific human nose. The realistic three-dimensional geometry of the nasal cavity is reconstructed from computer tomography (CT) scans. Identification of the region of interest, removal of artifacts, segmentation, generation of the .STL file and the triangulated surface grid are performed using the software packages ImageJ, meshLab, and NeuRA2. An unstructured computational volume grid with approximately 15 million tetrahedral grid cells is generated using the software Ansys ICEM-CFD 11.0. An unsteady Eulerian-Lagrangian formulation is used to describe the airflow and the spray dispersion and deposition in the realistic human nasal airway using two-way coupling. A new solver called pimpleParcelFoam is developed, which combines the lagrangianParcel libraries with the pimpleFoam solver within the software package OpenFOAM 3.0.0. A large eddy simulation (LES) with the dynamic sub-grid scale (SGS) model is performed to study the spray in both a steady and a pulsating airflow with an inflow rate of 7.5 L/min (or maximum value in case of the pulsating spray) and a frequency of 45 Hz for pulsation as used in commercial inhalation devices. 10,000 mono-disperse particles with the diameters of 2.4 µm and 10 µm are uniformly injected at the nostrils. In order to fulfil the stability conditions for the numerical solution, a constant time-step of 10 −5 s is implemented. The simulations are performed for a real process time of 1 s, since after the first second of the process, all particles have escaped through the pharynx or they are deposited at the surface of the nasal cavity. The numerical computations are performed on the high-performance computer bwForCluster MLS&WISO Production using 256 processors, which take around 32 and 75 hours for steady and pulsating flow simulation, respectively. The study shows that the airflow velocity reaches its maximum values in the nasal valve, in parts of the septum and in the nasopharynx. A complex airflow is observed in the vestibule and in the nasopharynx region, which may directly affect the dispersion and deposition pattern of the spray. The results reveal that the spray tends to deposit in the nasal valve, the septum and in the nasopharynx due to the change in the direction of the airflow in these regions. Moreover, it is found that due to the pulsating airflow, the aerosols are more dispersed and penetrate deeper into the posterior regions and the meatuses where the connections to the sinuses reside.

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Simulation of sprayed particle deposition in a human nasal cavity including a nasal spray device

Cited by 91 publications

References 24 publications

Source and trajectories of inhaled particles from a surrounding environment and its deposition in the respiratory airway

Source and trajectories of inhaled particles from a surrounding environment and its deposition in the respiratory airway

Topical contrast agents to improve soft-tissue contrast in the upper airway using cone beam CT: a pilot study

Numerical Simulation of the Dispersion and Deposition of a Spray Carried by a Pulsating Airflow in a Patient-Specific Human Nasal Cavity

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