[Geysers] Benchtop geysers

[Bruce Jensen]

My son Nick and I have done something very similar to Paul's in almost every respect, except we used a Coleman propane gas stove for heat and suspended the flask over the flame, and no turns in the tube (but that's a fun idea!).  We kept the bottom of the tube just about 1/2 inch above the flask base.  We found similar results when modeling a fountain geyser, although when we kept the top of the tube above the pool level in the funnel (cone geyser model), we got an eruption about 8 feet high (!!!).  It's exciting.  We saved the parts, so maybe we'll have another go at it with Paul's variations.

~ Bruce Jensen

--- On Mon, 1/26/09, Paul Strasser <upperbasin at comcast.net> wrote:

> From: Paul Strasser <upperbasin at comcast.net>
> Subject: RE: [Geysers] Benchtop geysers
> To: "'Geyser Observation Reports'" <geysers at lists.wallawalla.edu>
> Date: Monday, January 26, 2009, 9:47 PM
> Hi.
> 
> About ten years ago my daughter and I built a remarkably
> successful geyser
> out of a 1000ml Erlenmeyer flask, a stout rubber stopper
> with a hole, and a
> section of copper tubing that exactly fit the hole.
> 
> To the top was attached (via some sort of glue-stuff like
> epoxy that
> withstood the temps) to a funnel that had a large diameter
> of about 5
> inches.  To the top of this we got some sort of weird
> plumber's plaster and
> built a slightly inclined circular collecting basin on a
> piece of thin board
> - how we attached the board to the funnel I don't
> recall, probably some of
> that plaster.  It was held upright by a large corrugated
> paper box of the
> appropriate dimension.
> 
> The copper tubing (about 1/4" diameter, I believe) is
> what we used for
> variations.  Here's how - we'd fill the flask with
> water to about 700 ml,
> stick the stopper (with copper tubing already pushed
> through the hole), set
> the flask on an electric heating element (cheap at Target,
> etc.) and turn on
> the juice.  
> 
> What was cool was how even modest variations in the tube
> affected the
> eruptions.  For instance, how far above the bottom of the
> flask do you have
> the end of the tube?  It mattered a great deal.  Also, the
> best results were
> with the tube bent into two complete 360 degree vertical
> rings before going
> straight up.
> 
> The result was like Tardy.  It would take a while for the
> water to heat up,
> but eventually you'd notice the water level dropping in
> the flask because
> it's rising in the tube.  Then you'd see the water
> begin to rise in the
> funnel, then drop, then rise (a la West Triplet).  Finally,
> when the water
> poured out onto the "collecting basin" it would
> erupt.  The highest drops
> were 8-12 inches. When the water was exhausted it would
> quickly suck back
> down into the flask (draining back from the inclined
> collecting basin), only
> to play again within a minute - with the water rising in
> the funnel, etc.
> What stopped it was the loss of water via spray and steam,
> so we'd just add
> 50 ml or so every few eruptions.
> 
> One thing - there were inevitable leaks. We finally placed
> another piece of
> cardboard just above the stopper and gently surrounded it
> with an old bath
> towel.  After 30 minutes it was rather damp, but better
> that than drips from
> steam and spray leaking onto the heating element.
> 
> It was fun.  
> 
> We have the data for the variations we tried, but
> they're in a box with a
> lot of Linda's 4th grade stuff.  
> 
> Paul Strasser
> 
> -----Original Message-----
> From: geysers-bounces at lists.wallawalla.edu
> [mailto:geysers-bounces at lists.wallawalla.edu] On Behalf Of
> Davis, Brian L.
> Sent: Monday, January 26, 2009 3:07 PM
> To: geysers at lists.wallawalla.edu
> Subject: [Geysers] Benchtop geysers
> 
> First, a brief introduction. I'm a 40 y.o. stay-at-home
> Dad in Indiana, who
> also has a PhD in physics, and teaches physics, geology,
> and astronomy at a
> local university here in Indiana (a state notably lacking
> in geothermal
> activity :( ). I finally took my family out to Yellowstone
> in the summer of
> '06, and tagged along behind a group of gazers (I had
> no idea they existed
> at the time) on a wonderful day, finding the bunch at
> Grand, and after that
> trailing them as they seemed to know what they were doing
> for a nice play
> from Oblong.
> 
> If I hadn't been hooked prior to that, I certainly was
> after. Thank you all
> for instilling the addiction in another person. I never
> spoke to any of
> you... but just listening to your verbal "play"
> during the geyser play was
> one of the best parts of a fantastic dawn-to-dusk day.
> 
> I'm coming out of lurking to ask opinions and
> additional information on
> constructing a "benchtop" model. This started out
> as a daughter's science
> fair experiment, but I realized I could end up doing a lot
> more with it
> personally after the fair. Here's the best paper
> I've found on it:
> 
> http://www.fmf.uni-lj.si/~planinsic/articles/LasicArticle.PDF
> 
> Note that this is a *very* simple model, but still
> interesting from the
> standpoint of educating folks. What I'm curious about
> is suggestions for
> variation and other measurements. I'm planning on
> making several "models",
> including a simple tube (as in the paper), a tube with a
> constriction
> (possibly a variable one, using a piece of soft tubing
> pinched externally),
> multiple paths or reservoirs, and probably a more realistic
> model of
> refilling from a already warmed reservoir (instead of the
> water draining
> back from the eruption directly into the plumbing). I would
> value any
> suggestions, comments, or critical comments on this idea.
> Not the science
> fair part - getting a model that erupts and has a single
> variable (like heat
> input) would be more than sufficient for that.
> 
> Thoughts I've had are what allows multiple plays like
> Grand, as opposed to
> single eruptions, or what it takes in terms of the plumbing
> system, heating
> rate, and recharge structure to generate a steam phase, and
> what keeps it
> from happening in others. Obviously some of these are going
> to be too
> difficult to do on a benchtop (no deep plumbing, no high
> pressures), but the
> idea is interesting to me.
> 
> Ideas? and thank you once again for waking up a flatlander
> several years ago
> - I still watch the videos I took that day, and love the
> conversations on
> this list.
> 
> -- 
> Brian Davis
> wanabe gazer in
> Indiana_______________________________________________
> Geysers mailing list
> Geysers at lists.wallawalla.edu
> 
> 
> _______________________________________________
> Geysers mailing list
> Geysers at lists.wallawalla.edu
>