The 3D Modeling System for Bioaerosol Distribution Based on Planar Laser-Induced Fluorescence.

Siying Chen,Yinchao Zhang,Yuanyuan Chen,Pan Guo,Huiyun Wu,He Chen

doi:10.3390/s21082607

Abstract

Although it is quite challenging to image and analyze the spatial distribution of bioaerosols in a confined space, a three-dimensional (3D) modeling system based on the planar laser-induced fluorescence (PLIF) technique is proposed in this paper, which is designed to analyze the temporal and spatial variations of bioaerosol particles in a confined chamber. The system employs a continuous planar laser source to excite the fluoresce, and a scientific complementary metal oxide semiconductor (sCMOS) camera to capture images of 2048 × 2048 pixels at a frame rate of 12 Hz. While a sliding platform is moving back and forth on the track, a set of images are captured at different positions for 3D reconstruction. In this system, the 3D reconstruction is limited to a maximum measurement volume of about 50 cm × 29.7 cm × 42 cm, with a spatial resolution of about 0.58 mm × 0.82 mm × 8.33 mm, and a temporal resolution of 5 s. Experiments were carried out to detect the PLIF signals from fluorescein aerosols in the chamber, and then 3D reconstruction was used to visualize and analyze the diffusion of aerosol particles. The results prove that the system can be applied to clearly reconstruct the 3D distribution and record the diffusion process of aerosol particles in a confined space.

Highlights

Bioaerosols usually refer to the aerosols containing biological particles such as bacteria, viruses, and pollen, which are strongly associated with human lives [1,2]
Cho et al developed a scanned planar laser-induced fluorescence (PLIF) system to detect the relative concentration of OH in multiphase combustion flow fields [13]
The laser plane at an angle of 60° was utilized as the excitation source to induce fluor of 3D distribution, which can promote further studies on the dynamics of biological aerosols

Summary

Introduction

Bioaerosols usually refer to the aerosols containing biological particles such as bacteria, viruses, and pollen, which are strongly associated with human lives [1,2]. Increasing attention has been directed toward the effects of indoor fungal bioaerosol exposure on health and safety, especially in an enclosed space [4]. The factors, such as airflows and walking activities of indoor occupants, may affect the variation of fungal and bacterial bioaerosols in indoor environments [5]. The laser-induced fluorescence (LIF) is a highly sensitive technique that can discriminate between different biological particles and non-biological particles and has been applied for effective detection and characterization of bioaerosols [6,7,8]. By scanning the laser sheet across different spatial locations, multiple images for 3D imaging can be effectively captured with the PLIF technique. Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations

Methods

Discussion

Conclusion