Hi Bill, I think you have misunderstood what I suggested, which was not a linear chain of charged droplets, but one of mere air ions (ultra low current point to plane corona discharge), only too far apart (due to the low current) to provoke any significant widening of the beam by sideways mutual repulsion. Due to the low field ~1kV/cm, the ions would drift relatively slowly at ~20 m/s. So the threads would really be narrow ion streams, this is what you had suggested initially BTW, and which I had dismissed a bit too hastily.
The problem I see now with the electrospray explanation is the same I had seen (mistakenly I now realize in your case of ultra low currents) with the ion stream explanation, namely lateral expansion. As the name implies, charged water droplets will explode by self-repulsion and evaporation into a spray of smaller droplets, which will explode again etc... (see http://www.newobjective.com/electrospray/ ), so this would produce a relatively wide beam. Higher viscosity and non-evaporating oil droplets may behave differently, but I don't think electrospraying water or an aqueous solution can produce a narrow beam or thread as you observe. Let me know if the above makes any sense. Michel ----- Original Message ----- From: "William Beaty" <[EMAIL PROTECTED]> To: <vortex-l@eskimo.com> Sent: Sunday, June 24, 2007 8:30 AM Subject: Re: [Vo]:Goose bumps at the surface of a polarized liquid submitted to a field >> On Tue, 12 Jun 2007 10:36:57 +0200, "Michel Jullian" <[EMAIL PROTECTED]> >> wrote: >> >> >About the low current phenomenon, it occurs to me that a sufficiently >> >low current ion stream, where the ions would form a clearly discrete >> >dotted line rather than a continuous-looking stream, would not expand >> >sideways by self repulsion as we have been assuming all along. Each ion >> >would just follow the previous one at comfortable distance, only >> >sigzaging slightly along the line of maximum field while it collides >> >with neutrals every micron or so. Could this reconcile the ion wind >> >theory with your observations? > > Yes. I later found that the emission of a linear chain of charged > particles is called "electrospray." If a charged droplet is upon the > surface of a metal electrode, then at sufficient high fields the droplet > is distorted into a cone, a "Taylor cone." And when the tip of the cone > becomes sharp, then it emits a charged droplet. The droplet shields the > portion of the cone below it, so the sharp tip recoils, but only until the > droplet is pushed away. Then the field grows strong again and the sharp > tip spits out another charged droplet in an evenly-spaced sequence. > > Damp hair fibers definitely create better "threads" than very dry hair > fibers. I originally assumed that this was due to conductivity of wet > hair. But now I suspect that microscopic water droplets are being > emitted. > On the other hand, when a sharp liquid cone starts emitting a charged > fiber, that's called "electrospinning." Viscous liquids applied to > charged metal electrodes apparently will send out "spider webs" > spontaneously. > > > (((((((((((((((((( ( ( ( ( (O) ) ) ) ) ))))))))))))))))))) > William J. Beaty SCIENCE HOBBYIST website > billb at amasci com http://amasci.com > EE/programmer/sci-exhibits amateur science, hobby projects, sci fair > Seattle, WA 425-222-5066 unusual phenomena, tesla coils, weird sci >
