Atmospheric humidity and particle charging state on agglomeration of aerosol particles

Yuanping He, Zhaolin Gu, Weizhen Lu, Liyuan Zhang, Tomoaki Okuda, Kentaro Fujioka, Hui Luo, Chuck Wah Yu

Research output: Contribution to journalArticle

Abstract

Formation of haze is a phenomenon dependent on the relative atmospheric humidity and concentration of aerosol particles. The physical and chemical reactions on particle surfaces would lead to variations in particle sizes. This paper focuses on the physical behaviour of aerosol particles under the influence of atmospheric humidity, which produces liquid bridging forces and electrostatic interactions among particles. By water absorption experiment, a correlation between relative humidity (RH) and water content on particles was obtained. Through theoretical derivation, a relationship between the relative humidity and humidity ratio was established for calculating liquid bridging forces. The findings from experiments on atmospheric particles charging, showed most aerosols were negatively or positively charged and the average charges on these particles was more than one. An extended soft-sphere discrete element method (DEM) was used to simulate the evolution of aerosol particles, encapsulated in water vapour by considering liquid bridging forces, electrostatic interactions and Brownian forces. Results suggest that the agglomeration rate of particles would increase with a rise in the atmospheric humidity due to the increased liquid bridging forces that enhance the agglomeration velocity. The higher humidity would enhance the ionization on particle surfaces, which could affect electrostatic interactions. This paper provides an insight of a mechanism for formation of haze in atmosphere.

LanguageEnglish
Pages141-149
Number of pages9
JournalAtmospheric Environment
Volume197
DOIs
Publication statusPublished - 2019 Jan 15

Fingerprint

atmospheric particle
agglomeration
aerosol
liquid
haze
relative humidity
humidity
discrete element method
chemical reaction
atmospheric humidity
particle
water vapor
ionization
experiment
water content
particle size
atmosphere

Keywords

  • Aerosol particles
  • Agglomeration rate
  • Atmospheric humidity
  • Electrostatic interactions
  • Haze formation
  • Liquid bridging forces
  • Particle charging

ASJC Scopus subject areas

  • Environmental Science(all)
  • Atmospheric Science

Cite this

Atmospheric humidity and particle charging state on agglomeration of aerosol particles. / He, Yuanping; Gu, Zhaolin; Lu, Weizhen; Zhang, Liyuan; Okuda, Tomoaki; Fujioka, Kentaro; Luo, Hui; Yu, Chuck Wah.

In: Atmospheric Environment, Vol. 197, 15.01.2019, p. 141-149.

Research output: Contribution to journalArticle

He, Yuanping ; Gu, Zhaolin ; Lu, Weizhen ; Zhang, Liyuan ; Okuda, Tomoaki ; Fujioka, Kentaro ; Luo, Hui ; Yu, Chuck Wah. / Atmospheric humidity and particle charging state on agglomeration of aerosol particles. In: Atmospheric Environment. 2019 ; Vol. 197. pp. 141-149.
@article{1ab8e8a1ee9e4135815b18faa7a51bf7,
title = "Atmospheric humidity and particle charging state on agglomeration of aerosol particles",
abstract = "Formation of haze is a phenomenon dependent on the relative atmospheric humidity and concentration of aerosol particles. The physical and chemical reactions on particle surfaces would lead to variations in particle sizes. This paper focuses on the physical behaviour of aerosol particles under the influence of atmospheric humidity, which produces liquid bridging forces and electrostatic interactions among particles. By water absorption experiment, a correlation between relative humidity (RH) and water content on particles was obtained. Through theoretical derivation, a relationship between the relative humidity and humidity ratio was established for calculating liquid bridging forces. The findings from experiments on atmospheric particles charging, showed most aerosols were negatively or positively charged and the average charges on these particles was more than one. An extended soft-sphere discrete element method (DEM) was used to simulate the evolution of aerosol particles, encapsulated in water vapour by considering liquid bridging forces, electrostatic interactions and Brownian forces. Results suggest that the agglomeration rate of particles would increase with a rise in the atmospheric humidity due to the increased liquid bridging forces that enhance the agglomeration velocity. The higher humidity would enhance the ionization on particle surfaces, which could affect electrostatic interactions. This paper provides an insight of a mechanism for formation of haze in atmosphere.",
keywords = "Aerosol particles, Agglomeration rate, Atmospheric humidity, Electrostatic interactions, Haze formation, Liquid bridging forces, Particle charging",
author = "Yuanping He and Zhaolin Gu and Weizhen Lu and Liyuan Zhang and Tomoaki Okuda and Kentaro Fujioka and Hui Luo and Yu, {Chuck Wah}",
year = "2019",
month = "1",
day = "15",
doi = "10.1016/j.atmosenv.2018.10.035",
language = "English",
volume = "197",
pages = "141--149",
journal = "Atmospheric Environment",
issn = "1352-2310",

}

TY - JOUR

T1 - Atmospheric humidity and particle charging state on agglomeration of aerosol particles

AU - He, Yuanping

AU - Gu, Zhaolin

AU - Lu, Weizhen

AU - Zhang, Liyuan

AU - Okuda, Tomoaki

AU - Fujioka, Kentaro

AU - Luo, Hui

AU - Yu, Chuck Wah

PY - 2019/1/15

Y1 - 2019/1/15

N2 - Formation of haze is a phenomenon dependent on the relative atmospheric humidity and concentration of aerosol particles. The physical and chemical reactions on particle surfaces would lead to variations in particle sizes. This paper focuses on the physical behaviour of aerosol particles under the influence of atmospheric humidity, which produces liquid bridging forces and electrostatic interactions among particles. By water absorption experiment, a correlation between relative humidity (RH) and water content on particles was obtained. Through theoretical derivation, a relationship between the relative humidity and humidity ratio was established for calculating liquid bridging forces. The findings from experiments on atmospheric particles charging, showed most aerosols were negatively or positively charged and the average charges on these particles was more than one. An extended soft-sphere discrete element method (DEM) was used to simulate the evolution of aerosol particles, encapsulated in water vapour by considering liquid bridging forces, electrostatic interactions and Brownian forces. Results suggest that the agglomeration rate of particles would increase with a rise in the atmospheric humidity due to the increased liquid bridging forces that enhance the agglomeration velocity. The higher humidity would enhance the ionization on particle surfaces, which could affect electrostatic interactions. This paper provides an insight of a mechanism for formation of haze in atmosphere.

AB - Formation of haze is a phenomenon dependent on the relative atmospheric humidity and concentration of aerosol particles. The physical and chemical reactions on particle surfaces would lead to variations in particle sizes. This paper focuses on the physical behaviour of aerosol particles under the influence of atmospheric humidity, which produces liquid bridging forces and electrostatic interactions among particles. By water absorption experiment, a correlation between relative humidity (RH) and water content on particles was obtained. Through theoretical derivation, a relationship between the relative humidity and humidity ratio was established for calculating liquid bridging forces. The findings from experiments on atmospheric particles charging, showed most aerosols were negatively or positively charged and the average charges on these particles was more than one. An extended soft-sphere discrete element method (DEM) was used to simulate the evolution of aerosol particles, encapsulated in water vapour by considering liquid bridging forces, electrostatic interactions and Brownian forces. Results suggest that the agglomeration rate of particles would increase with a rise in the atmospheric humidity due to the increased liquid bridging forces that enhance the agglomeration velocity. The higher humidity would enhance the ionization on particle surfaces, which could affect electrostatic interactions. This paper provides an insight of a mechanism for formation of haze in atmosphere.

KW - Aerosol particles

KW - Agglomeration rate

KW - Atmospheric humidity

KW - Electrostatic interactions

KW - Haze formation

KW - Liquid bridging forces

KW - Particle charging

UR - http://www.scopus.com/inward/record.url?scp=85055435353&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85055435353&partnerID=8YFLogxK

U2 - 10.1016/j.atmosenv.2018.10.035

DO - 10.1016/j.atmosenv.2018.10.035

M3 - Article

VL - 197

SP - 141

EP - 149

JO - Atmospheric Environment

T2 - Atmospheric Environment

JF - Atmospheric Environment

SN - 1352-2310

ER -