JSC (AV) - Skylab 4 - Liquid Floating Zone - TV 101 Part 4

Description

FR A226 SKYLAB 4 KINESCOPE TAPE 10, PART 2 of 2 and expect to get it all over on the right... can you see I've tried to excite two different modes now, one of longitudinal oscillation and (garble) now also. We are relatively clean interface on this one this time we will be counter- rotating - by that, we mean one rod will go in one direction, the second rod in the opposite direction It will try to go at the nominal rate of 16 in. every 10 seconds, and what I'm trying to do now is make sure we have the axes of the two rotating rods completely aligned. There - that's good. Okay, here we go. And you see there's an awful lot of mixing in there, surprisingly enough, very early in the game they both - exchanged, and we got a pretty thorough mixing. Now while I have this fluid here, let's do one other thing. Let's just see if we can get a little clearer illustration than we had before of waves. Types of waves we're looking at here are called longitudinal waves. By that, we mean that the material moves back and forth in the same direction that the wave will travel, pretty much the same in the way sound travels in the air. Now the opposite kind of wave is called a transverse wave, and by that, we mean that the fluid, or medium, will move perpendicular or right-angles to the direction at which the wave travels. Application of that is the violin string. These are longitudinal, fluid just moving back and forth there's a good standing rate okay, we're gonna' go on now and try some which are a little larger in length and see what develops. Continuation here of TV 101. Okay, we're back here with the Grandaddy of them all. This is the biggie. We're working here with a gap of two inches, 10 cc's of water on each side, and first, we'll just take a look at a few oscillations, although I will go rather gingerly on these. Okay, we can see the natural frequency there which I could certainly amplify but I choose not to. Now you see, I can get out of phase with it and cause interference which merely regards harmonic, but I wish not to play with this too much now. Instead, we'll press on with the experiment. We will first rotate in the same direction. You'll notice in the clear bubble that there is a small air bubble included. The angle I can see on the bubble, it makes a very good lens to amplify uh make the here we go. That was the only way I could get it over there. Okay, we're gonna' go get a better rate - a little bit lower than the specified rate of 16 in. every 10 seconds for pulling Page 2 up the rod. After watching the last one, with a gap of only 1-3/8", I am sure it's obvious that that speed would be disastrous. Okay, here we go. Well, where are we. Hold on, let me back you off. I got a good view, but you don't. Center you up There we go. Okay, now - you have only one angle on that - the angle I can see is that the light (garble) fluid - the violet - has gone all the way around on the outside, but the clear fluid has penetrated up the axis. Okay, here we go. Well, look at that. Now I can get the standard mode of oscillation. Hang in there Okay, let's see if we can get this back together and finish it , up to an extent anyway. There we go. Okay, we still have a little rotation left. There's the interesting oscillation - okay, any faster than you see that I do get the one measure in stability which is just what you see in front of you, this C-shape which rotates. Notice damping times are much longer. Okay now, it's so much more unstable - it has a pinch instability. By that, we mean once it starts to neck down and the surface tension acts in a way so as to accelerate that inch or that necking down, and we end up with two hemispheres. There's a good standing rate by that we mean of the modes or (garble) points that are made in the same locations. There is a primary mode probably is the lowest we could get - why don't we just pass this fluid back and forth? One side throwing it back and forth to the other - okay, let's go for a little higher. Okay, we'll set up for a counter rotation. Continuation of TV 101. We're back with one more this will be three separation - 20 cc's total of fluid counter-rotation. Now we'll have to use a little inertia to get these together - there we go. There's a good fundamental mode. Okay, here we go. Now here's that asymmetry which has been dominant. You nicely (garble) now I'm gonna' hold up here and let it stabilize. Noticely how quickly it mixes. Now one thing that may be causing relatively quick mixing is that we have the end plate is not completely parallel so that you do get a little motion along the axis as seen by (garble) right next to the plate, so that could induce a little bit more than you might get if it were perfectly parallel. But we're not very far out. Okay, it's stabilized out now, we'll try it again. This is a continuation of TV 101. What we're trying to create is - is super column. We've tried to see what is the maximum length we could get, and you'll see as I move, that there is a critical dimension - critical length, here - probably a length in diameter - however, it's strongly influenced by how much inertia I have - happen to have in the water at the time, or motion. If I can get this perfectly still and draw it out, which I'm doing ever SO slow now, I could probably go a little bit further Page 3 than I will be able to with these small oscillations in there. But there is a critical length, I believe, I although I've not calculated it where any small perturbation would cause it to neck down - you see it's starting to neck down on the right okay now I've got a one-rod out to the maximum amount. Now I'll start trying to withdraw the rod on the right. You'll notice that it's started to neck down a little bit there on the right - moreso than on the left, and I believe the reason there is that I had put Critox - which is a lubricant and will not allow the water to wet the surface. I put that all around the edge here and probably not as much got on the edge of this disc, SO you see, this is' really a wider column on the left side than on the right, so I'll all the necking down will occur on the right. Okay, it's starting to go down. Okay, now I had to move the fluid down in order to stop it, because once it necks down, we've got ourselves one small hemisphere and one large one. Of course, the fundamental mode - the primary oscillation, if you will (garble) first order rather is just one of mass motion back and forth, very slow, very lazy.

Collection

Records of the National Aeronautics and Space Administration

Series

Moving Images Relating to Documentary Stock Footage