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

Description

FR A231 SKYLAB 4 KINESCOPE TAPE 12, PART 2 of 3 TV 101. Okay, we're gonna' pick up again here - with one that we had done once before, however, it WS not done after we had made the modifications to the plates and seeing as we're going to use this particular run as a baseline for some of the things we're gonna' do later on, I feel it's worthwhile doing over again. This will be the one with the medium distance. That's 1-3/8" and 14 cc's of fluid. Now all rotations that we do from here on will be in the same direction both sides. And, we'll start out very slowly okay, we'll let this stabilize, and go for a medium speed. Now there's an asymmetry that's kind of interesting it's transferred its oscillation from one of rotation about the axis to motion along the axis. Okay, one more. This time we're gonna' try the same as we've just seen previously, that is, rotation of both rods, same direction, 14 cc's of fluid, 1-3/8" separation, but we'll try it with bubbles immersed in the fluid, which I've gotten that way by just shaking up a little air and little water in a syringe. And we'll watch what happens. Although we don't have gravity coming in here, we do have centrifugal force, and let's see if you can guess what the bubbles will do. Here we go, very slowly and the fluid continues to rotate and you see where the bubbles start to congregate. As we go along here, we'll find them all along the axis of rotation. Okay, now watch that. You'll see the bubbles tend to stay on the original axis - that's the axis of rotation of the fluid, not the center of the fluid. Here we find the centrifugal force takes the place of gravity, so in the same way, the bubbles in gravity tend to rise to the surface, sure they will tend to rise the opposite direction which the fluid is being pulled, in this case, the centrifugal force pulling it out, the bubbles move in. Here again, you note the bubbles are moving relative to the fluid so as to stay in the center of the axis of rotation. Looks as if we've lost a fair number of them let's just see if I can't illustrate my - let me make a little subcue injection here - the medical world will be astounded and you'll note with bubbles this size, they tend to accumulate, or tend to coalesce not that the other ones don't also, but these just do it at a faster rate and are more visible. Well, we lost a little well, that's too bad. We'll have to add a little here now those will probably still very slowly move to the center because we do have just a little bit of rotation remaining in the fluid. Page 2 A231 Let's see what happens now with vibration. The bubbles tend to move in the direction of a way, they tend to stay away from the disc which is the forcing function which is the moving of fluid, moving the fluid. They're just clinging on to it with all they can okay, enough of bubbles. Okay, here we are we are gonna' try this now with a little bit of ice in the center. This is untried or unproven technique. We have a rod of frozen ice there in the center and we'll see if we can get some water around it, without nubbing at all. Okay, it's far below the desirable amount but let's go ahead and give it a whirl, so to speak. Rotation in the same direction, both rods. Okay, now you see the ice tends to act in the same way as the bubbles did, ice being a little bit less tense than water, will also tend to move in the opposite direction in which the water is forced, in this case, centrifugal force. It's causing the motion, and if I can keep this probably at about the same rate oops, not as predictable as you'd like. Get these fellows together here makes it tough when it's off axis okay. There we go. Now let's try this again. You see a pretty much, as long as you got a relatively straightforward flow - it tended to remain right there in the center. Yeah, I think that's about all we can ask of this one. It did show it, although it was not a steady state. Okay, here we have on our left, our old friend, a little colored water on the end of the disc and rods, and you see it behaves the same way as we've seen it behave before. Over on the right, we have some water with just a little bit of soap on in it. Opaque, but it's essentially the same density, but with a little bit of soap. Now we just saw a way in which we could demonstrate that the surface tension of that fluid is considerably less to that of the fluid without the surface tension. If we could watch this long enough, we could figure out what the beating would be between the two and the difference of the frequency. You also notice that the one on the right damps quite a bit quicker. Once again, it should think a little bit about vibration and damping. Once again (garble) spring constant the greater the affect the damping forces have. Okay, let's see what happens if we give it a little higher frequency vibration. Nothing characteristic to mention there characteristic form and here, which is slightly different. It has somewhat the same overall characteristic, but I'm sure when you perturb compare the two, one right next to the other, they will be different. Page 3 A231 Okay, let's join them together and see what happens. Okay, let's vibrate this a little bit before we de-rotate think you'll see little parts of dried surface soap with nothing (garble) will gradually get dissolved back in Okay, let's start the rotation now. Slow, both in the same direction hold it there and then we'll come on back and do the same you know, the whole total column has reduced its surface tension as the result of the soap in the water mixing and you saw that it damped out rather quickly, much more quickly than we've seen with the other columns. But what the reduced surface tension, it's unable to sustain the same rotations which we've seen before let's try and link this fellow up again kind of get this center of mass across the axis he'll be in the right place now a little late. There we go. Once again. Very slowly. Now increase it a bit let's try a single rod rotation on the right. See how quickly it necks down? The fluid on the right starts rotating and necks down a little bit, and it shears right off as the fluid on the left is not rotating. Surface tension doesn't permit the fluid to retain a nearly uniform column of fluid all the way across, once it starts necking down and you have a rotation only on one side. It just enhances it and off it goes. Let's try that on the left now. There, we lost a little. Well, you win a few and lose a few. Judging from this, I would say this is the end of this demonstration.

Collection

Records of the National Aeronautics and Space Administration

Series

Moving Images Relating to Documentary Stock Footage