Environmental Dust Particles Repelling from A Hydrophobic Surface under Electrostatic Influence

Abstract

Environmental dust particles repelling from a hydrophobic surface under the electrostatic influence are considered and the dynamics of the dust particles are analyzed incorporating the high speed camera. The velocity of the repelled dust particles are formulated using the force balance incorporating the forces associated with the electrostatic repulsion, particle adhesion, particle drag, and the inflight particles interaction under the charge influence. The functionalized silica particles are deposited on the glass surface towards achieving a hydrophobic wetting state on the surface. An electronic circuitry is designed and built while generating the electrostatic effect, in the pulse form, on the dust particles located on the surface of the hydrophobic plate. Findings revealed that functionalized silica particles deposited surface results in hydrophobic wetting state with contact angle in the order of 158° ± 2° and contact angle hysteresis of 2° ± 1°. The electrostatic impulsive force generated on the plate surface enables to repel most of the sizes of the dust particles; however, some of the small dust particles remain as the residues on the surface after the electrostatic influence. The dust particle velocity predicted from the analytical formulation agrees with that obtained from the high speed camera data. The pinning force of the small size particles (0.6 µm≤), due to adhesion on the surface, is found to be larger than the average size particles (∼1.2 µm), which in turn, suppresses these particles repelling from the surface under the electrostatic influence. The residues of the dust particles on the as received glass surface after dust repelling are more than those residues on the hydrophobic surface. This behavior is associated with the dust particles adhesion on the surface. Consequently, hydrophobic wetting state on the plate surface improves the dust particle repelling from the surface.

Environmental dust repelling from hydrophobic and hydrophilic surfaces under vibrational excitation

“…2and 3are given in Appendix 1. Equations (2) and 3are solved numerically to obtain the dust particle displacement on the plate surface.…”

“…This is particularly true for solar panels located in the near region of desert environments; in which case, regular dust storms elevate technical challenges for cost effective mitigating dust from panel surfaces. Several techniques are introduced to clean dusty surfaces and some of these include electrostatic repelling 1,2 , brushing 3 , water splashing 4 , air jet blowing 5 , droplet rolling/sliding 6 , etc. Although some of the techniques introduced for dust mitigation are effective, they may find limited applications due to scarcity of clean water or expensive air compression.…”

“…At very high frequency or sound intensity, structural damage of the dusty surface and other accessories can possibly occur 7 . On the other hand, dust particles possess various elements and compounds such as Na, K, Ca, Mg, Fe, S, Cl, O 2 . Some of the elements form non-stoichiometric compounds in the dust particle, such as Na x Cl y , or Ca x Cl y , and non-stoichiometric compounds contribute to the charges of the dust particles.…”

A water droplet-cleaning of a dusty hydrophobic surface: influence of dust layer thickness on droplet dynamics

“…The electrodynamics affect can be utilized for self-cleaning applications of surfaces by rolling/sliding droplets 8 . In addition, electrostatic charges can be used to repel the dust particles from the surfaces 9 ; however, depending on the electrostatic force generated on the surface, the particles repelling creates dust cleaning effects on surfaces. Introducing electrostatic repelling force on the hydrophobic surface creates more effective dust removal than that of the hydrophilic surfaces.…”

“…Introducing electrostatic repelling force on the hydrophobic surface creates more effective dust removal than that of the hydrophilic surfaces. This behavior is attributed to the reduced adhesion between the dust and the hydrophobic surface 9 . Moreover, the lateral force related to the adhesion under surface tension plays a major role in droplet behavior on the surface.…”