Three dimensional tracing of a charged particle by electrostatic detection

Genc, Erdem; Mölleken, Andre; Tarasevitch, Doris; Utzat, Detlef; Nienhaus, Hermann; Möller, R.

doi:10.1063/1.5093988

Cited by 8 publications

(5 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have developed an experimental scheme that not only allows us to measure the charge before and after the contact with the surface but also enables us to follow the dynamics in real time. The setup provides a resolution better than 1 μs in time and about 6000 electrons or 1 fC for the charge ( 20 ). To study the motion and the contact electrification, gold spheres with 1 mm in diameter are dropped through a small orifice into a parallel plate capacitor.…”

Section: Resultsmentioning

confidence: 99%

Dynamics of contact electrification

et al. 2021

Self Cite

View full text Add to dashboard Cite

Although the electrical charging of objects brought into contact has been observed for at least 2000 years, the details of the underlying mechanism are still not yet fully understood. The present paper deals with the very basic process of contact electrification between two metals. We have developed an experimental method to follow the charge of a small sphere bouncing on a grounded planar electrode on a time scale down to 1 μs. It reveals that the sphere is discharged in the moment of contact, which lasts about 6 to 8 μs. However, at the very moment of disruption of the electrical contact, it regains charge far beyond the expectation according to the contact potential difference. The excess charge rises with increasing contact area.

show abstract

Section: Resultsmentioning

confidence: 99%

Dynamics of contact electrification

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, insulating grains do not discharge upon contact. This even holds for metal spheres, if their surface is not extremely cleaned from any contamination (Genc et al 2019;Kaponig et al 2020). A dimer or a more complex aggregate still hold charges on their surface.…”

Section: Charge Driven Aggregation and Stabilitymentioning

confidence: 99%

A Smoking Gun for Planetesimal Formation: Charge Driven Growth into a New Size Range

Teiser,

Kruss,

Jungmann

et al. 2021

Preprint

View full text Add to dashboard Cite

Collisions electrically charge grains which promotes growth by coagulation. We present aggregation experiments with three large ensembles of basalt beads (150 µm − 180 µm), two of which are charged, while one remains almost neutral as control system. In microgravity experiments, free collisions within these samples are induced with moderate collision velocities (0 − 0.2 m s −1 ). In the control system, coagulation stops at (sub-)mm size while the charged grains continue to grow. A maximum agglomerate size of 5 cm is reached, limited only by bead depletion in the free volume. For the first time, chargedriven growth well into the centimeter range is directly proven by experiments. In protoplanetary disks, this agglomerate size is well beyond the critical size needed for hydrodynamic particle concentration as, e.g., by the streaming instabilities.

show abstract

“…To this end, experiments are performed at the minimum threshold shear velocity u *ft , so that only one particle at a time enters the cup, thus enabling measurements of the charges of single particles. For details on the charge measurement we refer to Genc et al (2019) andJungmann et al (2021). Each experiment is performed for about 10 minutes, and no particles with a charge magnitude smaller than 0.2 • 10 5 e can be detected.…”

Section: Estimating the Particle Charge In The Experimentsmentioning

confidence: 99%

Lifting of Tribocharged Grains by Martian Winds

Kruss¹,

Salzmann²,

Parteli³

et al. 2021

Planet. Sci. J.

View full text Add to dashboard Cite

It is a long-standing open question whether electrification of wind-blown sand due to tribocharging—the generation of electric charges on the surface of sand grains by particle–particle collisions—could affect rates of sand transport occurrence on Mars substantially. While previous wind tunnel experiments and numerical simulations addressed how particle trajectories may be affected by external electric fields, the effect of sand electrification remains uncertain. Here we show, by means of wind tunnel simulations under air pressure of 20 mbar, that the presence of electric charges on the particle surface can reduce the minimal threshold wind shear velocity for the initiation of sand transport, u *ft, significantly. In our experiments, we considered different samples, a model system of glass beads as well as a Martian soil analog, and different scenarios of triboelectrification. Furthermore, we present a model to explain the values of u *ft obtained in the wind tunnel that is based on inhomogeneously distributed surface charges. Our results imply that particle transport that subsides, once the wind shear velocity has fallen below the threshold for sustained transport, can more easily be restarted on Mars than previously thought.

show abstract

Three dimensional tracing of a charged particle by electrostatic detection

Cited by 8 publications

References 17 publications

Dynamics of contact electrification

Dynamics of contact electrification

A Smoking Gun for Planetesimal Formation: Charge Driven Growth into a New Size Range

Lifting of Tribocharged Grains by Martian Winds

Contact Info

Product

Resources

About