Odds and ends

[Mark]

http://www.physics.lsa.umich.edu/demolab/demo.asp?id=90
http://tinyurl.com/y6yhfc
http://tinyurl.com/ykkvwc
http://www.oberlin.edu/physics/catalog/ ... siren2.jpg

[Mark]

I have picked well over a 150 grapefruit off of my 3 trees last month. There's probably 200 more up there. I even have this pole with a cup and tines that is about 8 feet long. I slid some segments of my red silicone fuel tubing over the tines so that the fruit are not scratched or punctured. I also have a ladder and yet I will never get the very highest fruit because branches are in the way and it's takes time to find the right angle of attack and how to position yourself.
It comes to mind that pulsejet land is quite like this. All the low hanging fruit has been picked.
Mark
http://www.madprofessor.net/Picture%206-3.jpg

[Jim Berquist]

Monkey! You need a Monkey!!!!

With a P.J. Back Pack......He pick your fruit and in the winter he could fly around the trees to word off the frost.......and check for bugs........

Jim

[Mark]

Doodling with these little hollow all thread segments/"potential gas tanks" reminded me it would be fun to build a small pulsejet with a sequestered fuel tank, the tank somewhere merged/situated internally, away from prying eyes. Then it would seem enchanting as to the source of it's power in some way perhaps. In appearances it might seem more of a pulsating rocket.
And then too, as mentioned, a smallish lightweight pulsejet launched like a bottle rocket into the sky for a short flight would be entertaining.
One design to try might be to "simply" spoke a tube filled with fuel up one end of a straight pipe. This would create the more restricted tailpipe section while having the fuel spray out the forward end, heat driven as the pulsejet runs. Or you could oversize the combustion chamber a bit or lay the tubing against one side of the internal wall of the combustion chamber or tailpipe even. Or perhaps you could find some thin-walled tubing and just spiral it internally to hold fuel if it didn't dampen the resonance. There must be some fun way to do it.
Of course we have seen the tank situated like a nose cone just in front of the intake but that's already been done.
Mark
PS We can imagine another scenario closer to home, that of a jam jar with it's internal supply of fuel boiling away merrily until the heating throws everything out of balance or you need water cooling or tender loving care to keep it going. On a good cool day my 2.5 gallon piglet snorkeler will drink all it's fuel running full grease the entire time, perhaps 4 minutes or so. It breathes like a jam jar in that the exhaust is the only intake.

[Mark]

A few other perspectives of a snorkeled jam jar concept.
Mark

[Mark]

Just a few for review, the old days.
Mark

[Mark]

Today I bought an extension spring rated for 31.2 lbs / 14.2 kilos. After I cut/ground off the rings at both ends it left 13.75 inches of length. The diameter is 1 1/8 inches. I put a rubber stopper in one end and blew into the other end. It holds air and water perfectly with a caveat. If you get it sopping wet and flex the coils, as when I aired it out by just bending it, the spring starts to let air seep, kind of like an air stone. Water or alcohol must be very slippery whereas when the spring is not soaking wet it is lock air tight. You can spray methanol inside it thoroughly and it seems to hold air fine, it's just when you flex it and allow wetness to sit on the "seals" that it leaks somewhat. Hmmm.
If you have ever tried to bark a short tube such as this size, even a small leak will defeat the buildup of feedback, so I was happy to get it to bark. There are a few fun ideas I think would be worth trying with this "spring steel valve" of a sort.
I bet I could pull apart the spring at one end and slip in a reed valve on a washer and get it to rev up for one thing. Another thing I thought of was to install it on the front end of my 3 inch diameter plumbing pipe pulsejet and cork the tail end and spark/implulse start it. As the pulsejet fires, the sealed at one end spring on the front might be forced to flex/spring open and then breath enough to allow for a rev up. While the spring might not spring open very far, there is a lot of surface area if the spring opens ever so slightly along it's length.
I have included a bark from the spring steel tubing/duct. First I sprayed some methanol inside the spring and then lit it, a lighting of the tail.
Mark

[Mark]

To show it can bend.
Mark

[Mark]

Another purchase 9/16ths diameter. You might say it was an impulse buy. ha
Mark

[Mark]

Humble beginnings of resonance with the smaller 9/16ths spring. A funny thing, I lit it when I had it in a complete loop just to see what it would do and it made an interesting pop as the flame front looped around and out the other end. I couldn't get it to do it again, but it was odd in that there was so much leakage being bent a full 360 degrees.
These sounds are of it in the natural straight length spring position, pictured next to it's big brother.
Mark

[Mark]

One other odd thing, I bought this other spring for a trampoline and it just screws/twists into the long spring quite easily but the funny thing is that it is a really good seal too! How very strange, although it is fortuitous for experimenting with a longer length or possible combustion chamber section. I couldn't pull them apart when twisted together. This short spring is rated for 48.2 lbs / 21.0 kilos. Yawn, I know.
Mark

[Mark]

http://www.mems.duke.edu/seminars/2006-spring.php

[Mark]

Vague but of interest.
Mark
http://tinyurl.com/y7wtey

[Mark]

Garden Torch (Orchos) - Stainless Steel with Wood
Garden torch - H 57, dia 2.75"
Sale:
Retail:
$35.99 Item #
65007
$39.99

http://tinyurl.com/ygbavf
http://livingcomforts.com/OutdoorAcc.html
http://tinyurl.com/yxfak6
http://tinyurl.com/yyto9k

[Mark]

I was toying with my springs and found I could walk/twist one onto my smudge pot even though it is much wider than the flat hole opening. Pictured is the short segment centered over the hole.
But the wider spring I bought did something unusual when I methylated the pot and spring for a light test. I walked the ~14 inch long spring off to one side of the flat hole in the smudge pot, forming a crescent opening where they connected. So the spring acted as a chimney for half the hole and the other half something of a non-snorkeled side port. It reved up at a faster rate than a jam jar and louder, something pretty good and burned all the hair off my fingers from the fire from the crescent opening.
Mark
The little nipple that holds the wick lifts out and that is how the pot looks, perhaps a little clearer than my picture.
http://tinyurl.com/yg3fe3