SwePub
Sök i LIBRIS databas

  Utökad sökning

WFRF:(He Junjia)
 

Sökning: WFRF:(He Junjia) > (2023) > Ionization Activity...

Ionization Activity Detected During Dark Periods in Long Air Positive Sparks

Zhao, Xiangen (författare)
Hong Kong Polytech Univ, Dept Bldg Environm & Energy Engn, Hong Kong, Peoples R China.
Becerra Garcia, Marley, 1979- (författare)
KTH,Elektroteknisk teori och konstruktion
Wang, Xiankang (författare)
State Grid Hubei Elect Power Co Ltd, Elect Power Res Inst, Wuhan, Peoples R China.
visa fler...
Liu, Yang (författare)
Huazhong Univ Sci & Technol, State Key Lab Adv Electromagnet Engn & Technol, Wuhan, Peoples R China.
Du, Yaping (författare)
Hong Kong Polytech Univ, Dept Bldg Environm & Energy Engn, Hong Kong, Peoples R China.
He, Junjia (författare)
Huazhong Univ Sci & Technol, State Key Lab Adv Electromagnet Engn & Technol, Wuhan, Peoples R China.
visa färre...
Hong Kong Polytech Univ, Dept Bldg Environm & Energy Engn, Hong Kong, Peoples R China Elektroteknisk teori och konstruktion (creator_code:org_t)
American Geophysical Union (AGU), 2023
2023
Engelska.
Ingår i: Journal of Geophysical Research - Atmospheres. - : American Geophysical Union (AGU). - 2169-897X .- 2169-8996. ; 128:10
  • Tidskriftsartikel (refereegranskat)
Abstract Ämnesord
Stäng  
  • The dark period in long air gap discharges has been assumed in the literature as the time between consecutive streamer current pulses when ionization and luminosity are absent. These dark periods are also present in natural lightning, in processes such as the inception and propagation of upward positive leaders, the development of needles, as well as transient luminous events in the upper atmosphere. Only recently, faint luminosity has been observed during dark periods, challenging this assumption. This paper aims to study any possible electrical activity during dark periods by means of experiments supported by computer simulation. Therefore, an experimental platform, including low-current measurements, Schlieren and standard photography as well as ultraviolet (UV)-photon detection was used to observe the electrical-optical-thermal characteristics of the dark period. A complementary numerical model was used to estimate the streamer space charge spatial distribution and its drift during dark periods. It is found that faint UV and visible light during the dark period is emitted exactly at the location of the low-density streamer stem channel. This process is accompanied by the generation of an electronic current in the order of hundred microamps to milliamps. The simulation results show that this ionization activity occurs due to strong reduced electric fields in the residual stem channel above 112 Td, which is mainly determined by a combination of applied voltage, space charge distribution, and localized heating. Thus, the presented results show that there is indeed ionization activity during dark periods in long air gaps, which maintains a continuous glow-like discharge.

Ämnesord

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Meteorologi och atmosfärforskning (hsv//swe)
NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Meteorology and Atmospheric Sciences (hsv//eng)

Nyckelord

positive spark
long air gap
dark period
ionization activity
ultraviolet irradiance

Publikations- och innehållstyp

ref (ämneskategori)
art (ämneskategori)

Hitta via bibliotek

Till lärosätets databas

Sök utanför SwePub

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy