The first problem was separation of some floatable wax-like substance from the fuel when it got cold. The stuff would clog up the wick and out it would go. This became easy to recognize as it would go out almost like clockwork after a certain amount of burntime. The exact amount of time would depend on the amount of contamination and the amount of fuel in the font, but for any given combination of contamination and fuel, it would go out after about the same amount of burn time. The solution when it happens is to just pour off whatever is floating on the top, and a good pre-emptive solution is to completly clean out the font a couple times a month.
The second issue was realated to the wind. In the winter here in New England, it gets windy. On top of that, the leaves have fallen from the trees so there is little to block the wind. Somewhere's around 25 MPH the lamp would go out. It got so bad that it would go out sometimes a dozen times a day. I became frustrated and temporarily replaced the street lamp with a much more weather hardy Kirkman #2 mounted on a post bracket.
Woody Kirkman, aware of my frustrations, send me a new #300 top end with a modified air intake system.
The standard air intake looks like this:
In the standard top, the air enters the opening between the air downtube and the short length of larger tube that surrounds it. The wind at times could blow directly into the tube.
The modified experimental intake Woody sent me looks like this:
In the experimental top the air intakes are relocated to the bottom of the larger tube, preventing wind from blowing directly into the air intake.
I replaced the standard top with the experimental top and tested it out. I am guessing the wind tolerance went up by 3-5 MPH. That improvement reduced my frustration level to the point where I left the 300 up.
However, there were still days and nights where we would get 30+ MPH winds and the lamp was not able to take that.
I often went out there in the cold (beer in hand of course) and watched the wind and how it would affect the flame.
What I typically saw was that when the wind would pick up the flame would rise, sometimes becoming 6-8 inches tall. When this happened it would become very smokey. I also noticed that on windy nights the globe would soot up very badly, whereas on calm nights it would stay clean.
This started me to thinking that the issue was not excess air being pushed into the globe, but a vacuum coming from the chiminey pulling much of the combustion air OUT of the globe. The smokey combustion was possibly the result of oxygen starvation.
The exhaust for the lamp is a chiminey with a domed cap over it. The exhaust air exits through the space between the dome and the top of the round chiminey.
When it gets windy, the wind blows through this same space. As it does, the wind's flow path is constricted somewhat by the presence of the dome and the chiminey.
If you watch a flowing brook or river, you will notice that the water on the banks is almost stationary whereas the water in the middle moves the fastest. What causes this is the friction of the stationary river bank makes the water near it flow very slowly, whereas the water in the middle is not influenced by the river bank.
If air enters this space at say 30MPH and is constricted to the center of the space, in order fo the air to get through and back out again, the velocity in the restricted space has to increase to get the same amount of air through a smaller space. This reduced path is a "venturi" similar to the opening in a carburator.
It seems counterintuitive, but when air velocity goes up as an airstream enters a venturi, the air pressure drops.
One can read about such an effect in great detail here :
"http://en.wikipedia.org/wiki/Bernoulli's_principle"
(Sorry, but the apostrope in the URL name messes up the clickable link feature on this forum)
The vacuum caused by the wind under the dome pulled was pulling the combustion air out of the globe and starving the flame.
Pondering this kept me up more than a few nights.
--- MORE TO FOLLOW SHORTLY ---
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