Numerical Study on the Particle Trajectory Tracking in a Micro-UV Bio-Fluorescence Sensor

Abstract

A micro-UV bio-fluorescence sensor was developed to detect primary biological aerosols including bacteria, bacterial spores, fungal spores, pollens, viruses, algae, etc. In order to effectively detect the bio-particles in a micro-UV bio-fluorescence sensor, numerical calculations were performed to adjust for appropriate flow conditions of the sensor by regulating the sample aerosols and sheath flow. In particular, a CFD-based model of hydrodynamic processes was developed by computing the trajectory of particles using commercially available ANSYS CFX-14 software and the Lagrangian tracking model. The established model was evaluated with regard to the variation of sheath flow rate and particle size. Results showed that the sheath flow was changed rapidly at the end of nozzle tip, but the sample particles moved near the center of aerosol jet for aerodynamic focusing with little deviation from the axis.

Long-term study on coarse mode aerosols in the Amazon rain forest with the frequent intrusion of Saharan dust plumes

“…However, sampling through an inlet is always non-ideal and, thus, creates sampling artifacts as well as biases the measurement results (von der Weiden et al, 2009). Representative aerosol analysis requires high aspiration rates (i.e., isoaxial and isokinetic conditions) and high 5 tube transmission efficiencies (i.e., minimized losses) (von der Weiden et al, 2009;Byeon et al, 2015). For the tube transmission, the most relevant particle loss mechanisms (i.e., diffusion, sedimentation, and inertial deposition) are strongly size dependent, and coarse mode aerosol particles, which are the focus of the present study, are particularly prone to the deposition-and inertial-related artifacts.…”

Long-term study on coarse mode aerosols in the Amazon rain forest with the frequent intrusion of Saharan dust plumes

“…The Amazon rain forest is of particular relevance in Earth system science. It represents a vulnerable ecosystem of global importance, which is increasingly disturbed by the combination of climate change and agricultural as well as infrastructural expansion (Davidson et al, 2012). In fact, the Amazon has been ranked as one of the potential tipping points in the global climate system (Lenton et al, 2008).…”