Experimental Analysis of Ultrasonic Multiple Scattering Attenuation through the Air with Fine Dust

Ukyong Woo,Homin Song,Hajin Choi

doi:10.3390/app11020694

Ukyong Woo, Homin Song + Show 1 more

Open Access

https://doi.org/10.3390/app11020694

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Abstract

In this study, we experimentally evaluated the application of multiple scattering theory for measuring ultrasonic attenuation. Based on the independent approximation theory, the method adopted for calculating the attenuation of coherent waves through air with fine dust is discussed. To obtain a scattering wavefield, a unique ultrasonic scattering hardware was developed, and signal processing schemes were suggested. Four cases of standard particle doses (0, 0.004, 0.008, and 0.012 g) were investigated inside a chamber. The results obtained from the experiments demonstrate that the proposed signal processing approach successfully calculates the scattering attenuation, which correlates well with the applied doses of fine dust. In addition, we discuss the irregular shape and composition of fine dust relative to the scattering cross-section.

Highlights

Fine dust particles in the air, such as particulate matter, have been a serious societal challenge worldwide [1,2,3]
Owing to the scattering attenuation obtained by the experiment, the number of fine dust particles per unit volume can be quantified with a scattering cross-section, based on Equation (4)
The experimental analysis of ultrasonic multiple scattering was performed to obtain the scattering attenuation triggered by fine dust particles in air

Summary

Introduction

Fine dust particles in the air, such as particulate matter, have been a serious societal challenge worldwide [1,2,3]. Airborne fine dust is a critical environmental issue and a potential threat to human health [4]. The accurate measurement of fine dust concentration is essential for human health. The proposed techniques for measuring the concentration of fine dust include the beta ray, gravimetric, light scattering, and semiconductor-based gas sensor methods [5]. The most widely used light scattering method is based on the light source phenomenon, where laser is scattered proportionally to the concentration of fine dust [8]. The gas sensor is based on the contraction and expansion effect, as well as the change in electrical resistance triggered by adsorption and desorption when fine dust contacts the surface of the semiconductor. Light scattering and gas sensors that provide fast data at relatively low prices have been widely applied in the field, they are susceptible to environmental factors such as relative humidity; the need for additional calibration procedures [9,10,11]

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Discussion

Conclusion