An Euler-type gas/particle two-phase flow numerical model is presented for simulating the deposition of particles of tens of microns. At this size range of particles, the dominant effect considered for deposition on the bottom surface is gravitational settling. The mass conservation equation for the particulate phase is developed and simulated to include convection, diffusion, and gravitational...

Particulates that deposit in the acinus region of the lung have the potential to migrate through the alveolar wall and into the blood stream. However, the fluid mechanics governing particle transport to the alveolar wall are not well understood. Many physiological conditions are suspected to influence particle deposition including morphometry of the acinus, expansion and contraction of the alve...

Extrathoracic deposition of inhaled particles (i.e., in the head and throat) is an important exposure route for many hazardous materials. Current best practices for exposure assessment of aerosols in the workplace involve particle size selective sampling methods based on particle penetration into the human respiratory tract (i.e., inhalable or respirable sampling). However, the International Or...

Inhalation of cigarette smoke particles (CSP) leads to adverse health effects in smokers. Determination of the localized dose to the lung of the inhaled smoke aids in determining vulnerable sites, and identifying components of the smoke that may be responsible for the adverse effects; thus providing a roadmap for harm reduction of cigarette smoking. A particle deposition model specific to CSP w...

BACKGROUND Epidemiological studies show that elevated levels of particulate matter in ambient air are highly correlated with respiratory and cardiovascular diseases. Atmospheric particles originate from a large number of sources and have a highly complex and variable composition. An assessment of their potential health risks and the identification of the most toxic particle sources would requir...

Differences in particle deposition patterns between human and rat lungs may be attributed primarily to their differences in breathing patterns and airway morphology. Heterogeneity of lung structure is expected to impact acinar particle deposition in the rat. Two different morphometric models of the rat lung were used to compute particle deposition in the acinar airways: the multiple-path lung (...

A multistage sampler was developed and tested to estimate regional deposition of aerosol in the human respiratory system. The motivation for this research is to improve our ability to estimate inhaled aerosol dose. Current methods for aerosol measurement and exposure/risk assessment are based on particle aspiration (e.g. inhalable PM) or on penetration to various regions of the respiratory syst...

There has been relatively little attention given on predicting particle deposition in the respiratory zone of the diseased lungs despite the high prevalence of chronic obstructive pulmonary disease (COPD). Increased alveolar volume and deterioration of alveolar septum, characteristic of emphysema, may alter the amount and location of particle deposition compared to healthy lungs, which is parti...

[1] A number of synthesis activities, mathematical modeling, and experiments on dry deposition of aerosol‐sized particles over forested surfaces point to three disjointed findings: (1) deposition velocities measured over tall forests do not support a clearly defined minimum for particle sizes in the range of 0.1–2 mm; (2) when measurements of the normalized deposition velocity (Vd ) are present...

During respiration, particles suspended in the air are inhaled and unless cleared by airway defences they can remain and affect lung health. Their size precludes the use of standard imaging modalities so we have developed synchrotron phase-contrast X-ray imaging (PCXI) methods to non-invasively monitor the behaviour of individual particles in live mouse airways. In this study we used these tech...