On Tuesday, September 13, 2022 at 10:20:03 PM UTC+2, Pangloss wrote:
...
> Sono piuttosto convinto che un fuoco all'aperto sia un probabile punto d'impatto dei
> fulmini perche' sopra alle fiamme vi e' una zona (ristretta) di aria ionizzata.
> Non eseguiro' in merito esperienze alla Franklin per ovvie ragioni (e per non essere
> scambiato per un piromane!).
Segnalo questo articolo sulla ionizzazione nelle fiamme:
(Ions in Flames, di H. F. Calcote,
DOI: 10.1007/978-1-4684-1938-2_8 )
Abstract - Originally, studies of ionization in flames were motivated by the
observation that in hydrocarbon flames, the ion concentration far exceeds
the value expected if ionization were due to thermal processes alone(1,2)
(see Table I). The objectives of these studies were to explain the source
of nonequilibrium ionization and to explore links between flame ionization
and the mechanism of flame propagation. An explanation of the source of
flame ions was found in the process of chemi-ionization.(2) This led to
further studies of the details of ionic reactions which occur in flames and
of flame reactions which can be induced by the addition of foreign elements.
Oltre alla ionizzazione termica, si prendono in considerazione la
chemi-ionization (produzione) e la chemical ionization (trasferimento).
Sul sito Springer c'è una preview:
https://link.springer.com/chapter/10.1007/978-1-4684-1938-2_8
Dello stesso autore c'è anche "Ion and electron profiles in flames"
sull'analisi della ionizzazione con sonde di Langmuir
doi.org/10.1016/S0082-0784(63)80071-5
Abstract - It is shown how Langmuir probes can be used in flames to obtain
not only the positive ion concentration but electron concentrations and
electron temperatures. ...
https://www.sciencedirect.com/science/article/abs/pii/S0082078463800715
Non so giudicarne l'attendibilità, ma ecco quanto dice (in fondo)
questo sito governativo americano che però punta sul fumo:
Lightning Causes Forest Fires. Can Forest Fires Cause Lightning?
Yes, smoke and carbon micro-particles, when introduced into the
upper atmosphere, can become the initiators of static. Sufficient
atmospheric static can spark discharge as lightning. Reports of
massive lightning storms in coastal Brasil, Peru and Hawaii have
been linked to burning of sugar cane fields. The late 90's Mexican
forest fires resulted in unusual lightning activity in the USA High
Plains area (Lyons, et al.) So too can dust in an enclosed
grain elevator create a static discharge. Recent reports (Orville, et al)
show the Houston TX petrochemical industry, discharging copious
amounts of hydrocarbons into the upper atmosphere, may be
responsible for higher-than-normal lightning activity in that area.
(National Lightning Safety Institute).
https://www.weather.gov/safety/lightning-myths
Ciao
Patrizio
> --
> Elio Proietti
> Valgioie (TO)
Received on Wed Sep 14 2022 - 17:32:31 CEST