Towards a qualified Computational Fluid Dynamics model to predict lung dose
2018 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE credits
Student thesis
Abstract [en]
Inhalation of drugs is an eective way to administrate drugs and treat medicalconditions. But the drug has to reach the deep lung to have an eect. There aretwo approaches to decide the amount of the inhaled substance which is reach-ing the deep lung, in vivo and in vitro but these approaches are expensive andtime consuming. A complement to these approaches are numerical simulationsvalidated against experimental data when possible.In this study a numerical simulation of nebulized aerosol in the mouth andthroat region carried out and validated against both in vivo and in vitro data.The PARI LC STAR nebulizer was used in the in vivo and in vitro study forcorrect comparison. Previous numerical studies with nebulized aerosol is onlyvalidated against in vitro data or not validated at all.The mouth-throat geometry used in the numerical simulations and the in vitrostudy is identical. This geometry originates from a MRI scan of a man withopen mouth. The nebulizer in this study produces an aerosol with MMAD of2m and GSD of 1.9, these values are used in the numerical simulation. TheCanadian standard inhalation prole is used in both the numerical simulationand in vitro experiment.ANSYS CFX 18.2 which is a commercial CFD software package is used for thenumerical analysis. A Lagrangian particle tracking scheme is employed and aone way coupling between the continuous and dispersed phase is used. Includedforces acting on the particles are drag and gravity. The ow in the mouth-throat region is transitional or turbulent. Turbulence is modelled with the lowReynolds Number (LRN) SST k ! turbulence model in this study.CFD and in vitro results are similar except an over deposition in the CFDsimulations. Fluctuations near the wall not considered in this study is themain reason of the over deposition. Throat deposition is larger in the in vivostudy. This implies that both CFD and in vitro experiments are not sucientto provide a correct prediction of lung dose. Further studies are needed to beable to investigate why CFD and in vitro does not correspond to in vivo throatdeposition.
Place, publisher, year, edition, pages
2018. , p. 36
Keywords [en]
CFD, Computational fluid dynamics, Particle deposition, Human throat, throat cast, in vivo, in vitro
National Category
Fluid Mechanics
Identifiers
URN: urn:nbn:se:ltu:diva-70173OAI: oai:DiVA.org:ltu-70173DiVA, id: diva2:1235818
External cooperation
AstraZeneca
Subject / course
Student thesis, at least 30 credits
Educational program
Engineering Physics and Electrical Engineering, master's level
Supervisors
Examiners
2018-08-312018-07-272025-02-09Bibliographically approved