WEBVTT - Wind Tunnels: More Important Than You Realize 0:00:01.120 --> 0:00:03.560 Welcome to Stuff You Should Know, a production of five 0:00:03.600 --> 0:00:12.840 Heart Radios How Stuff Works. Hey, and welcome to the podcast. 0:00:12.920 --> 0:00:17.720 I'm Josh Clark, there's Charles W. Bryant, and there's Jerry 0:00:17.800 --> 0:00:22.120 Woosh Roland over there is just getting worse and worse. 0:00:22.800 --> 0:00:28.640 This is Stuff You Should Know podcast wind Tunnel a 0:00:28.760 --> 0:00:31.560 dish m Aren't you glad we're not in the same 0:00:31.640 --> 0:00:36.960 room so that you couldn't smell my breath When I went, yeah, 0:00:37.040 --> 0:00:38.800 my daughter's gotten a bad habit of doing that, and 0:00:38.840 --> 0:00:40.960 she thinks it's funny. I'm like, it's really not of 0:00:41.080 --> 0:00:45.720 what of like breathing and someone's nose on purpose, like 0:00:46.520 --> 0:00:48.199 right in your face, and like no one, no one 0:00:48.240 --> 0:00:52.120 likes that. Yeah, she's she's just entered the age of 0:00:52.120 --> 0:00:57.760 what five to where that's something people do. Yeah, not 0:00:57.760 --> 0:01:00.600 not funny. Ever, I'll tell you what. These masks that 0:01:00.680 --> 0:01:02.560 we're all wearing, this is a real reckoning with your breath. 0:01:02.600 --> 0:01:05.120 THO wouldn't it? Oh my god, it's funny. It's like 0:01:05.120 --> 0:01:10.640 a it's like an hour by our slide into despair. 0:01:11.160 --> 0:01:13.760 You're like, I don't remember eating garlics. Yeah, it's like 0:01:13.800 --> 0:01:15.240 in the morning is like, oh man, this is great, 0:01:15.240 --> 0:01:16.800 and I love this mask. And later in the day 0:01:16.840 --> 0:01:20.319 you're you need that toothbrush. Yes, it's true. They say 0:01:20.360 --> 0:01:22.479 you can't smell your own breath and they are wrong. 0:01:23.800 --> 0:01:25.600 And I'm brushing my teeth now more than other because 0:01:25.600 --> 0:01:28.319 I'm scared to go to the dentist. Yeah. Same here. 0:01:28.360 --> 0:01:31.400 I'm also flossing like a mad person too. You're flossing 0:01:31.520 --> 0:01:33.440 right now, I can, I can hear it. Wow, that 0:01:33.520 --> 0:01:36.160 was the most pc thing I've ever said, is what 0:01:36.840 --> 0:01:40.920 I'm flossing like a mad person, not a madman. And technically, 0:01:41.000 --> 0:01:44.680 I guess not. I would have said like a mentally 0:01:44.720 --> 0:01:49.400 ill health person. Yeah, I think that's even bad. Who 0:01:49.400 --> 0:01:53.240 knows these days, right, that's right. Let's talk about wind tunnels. Okay, 0:01:53.320 --> 0:01:57.840 so we're talking wind tunnels. Um, and I had no 0:01:57.960 --> 0:02:00.840 idea how interesting wind to thos were. I had an 0:02:00.880 --> 0:02:02.720 inkling that they were going to that there was like 0:02:02.800 --> 0:02:06.560 more to wind tunnels than people realize, which is absolutely true. Um, 0:02:06.600 --> 0:02:09.880 but they're they're pretty, they're deep cut. Yeah, I mean 0:02:09.880 --> 0:02:11.920 there was way there's way more to them, and you 0:02:11.919 --> 0:02:13.919 can do way more with them and learn way more 0:02:14.000 --> 0:02:18.800 from them than I thought because my experience with wind tunnels. 0:02:18.840 --> 0:02:22.760 Like most people is seeing the cool TV commercial with 0:02:22.840 --> 0:02:25.919 the with the like green smoke flying over the car 0:02:26.160 --> 0:02:30.040 to demonstrate how aerodynamic it is. And to be sure, 0:02:30.080 --> 0:02:32.200 that is a very big part of what they use 0:02:32.240 --> 0:02:35.280 wind tunnels for. Yeah. Yeah, and Chuck, you know, you 0:02:35.360 --> 0:02:37.240 and I were in a commercial in a wind tunnel. 0:02:37.840 --> 0:02:39.919 I thought you might bring this up. That was a 0:02:39.960 --> 0:02:43.600 wind tunnel. Technically that that um indoor skydiving thing is 0:02:43.639 --> 0:02:46.519 a type of wind tunnel. It's a vertical wind tunnel. Yeah, 0:02:46.600 --> 0:02:48.800 if you guys haven't seen that. It's been a while 0:02:48.800 --> 0:02:50.400 since we promoted these things. We used to do these 0:02:50.440 --> 0:02:54.320 little shorts. Um no, this was different. Well no, but 0:02:54.360 --> 0:02:57.040 these were based on the shorts. Yeah. Yeah, we did 0:02:57.040 --> 0:03:00.160 these little shorts that we called interstitials. Did a lot 0:03:00.200 --> 0:03:02.400 of them, and to me, it's like the best video 0:03:02.440 --> 0:03:05.640 work we've ever done as a team. Um, I love 0:03:05.680 --> 0:03:08.640 don't be done. But that was just you. Um well, 0:03:08.680 --> 0:03:10.600 it was great. It was you in the room and 0:03:10.639 --> 0:03:14.959 it was this chair and you sort of played a character. Yes, 0:03:15.040 --> 0:03:18.000 go on, And some people have problems with the character 0:03:18.000 --> 0:03:19.520 because I thought you were making fun of a certain 0:03:19.560 --> 0:03:22.480 kind of person. Sure, that wasn't true. It was all 0:03:22.520 --> 0:03:26.040 very kind hearted and just funny. That was really great, 0:03:26.040 --> 0:03:28.280 Thank you. Sure. Uh and that chair still here in 0:03:28.280 --> 0:03:30.680 the office, right, Yes it is, and I believe my 0:03:30.760 --> 0:03:35.160 outfit still is. I'm waiting for the Smithsonian calm. So. Yeah. 0:03:35.200 --> 0:03:39.040 We did this um TV commercial for Toyota that was 0:03:39.200 --> 0:03:41.640 very much in the vein of those interstitials where we 0:03:41.640 --> 0:03:44.200 were in just all over Atlanta, in various parts of 0:03:44.280 --> 0:03:47.600 Atlanta doing funny things. That was l A. Remember well, no, 0:03:47.760 --> 0:03:51.400 this was again talking about the original interstitiause I'm so confused. 0:03:52.200 --> 0:03:53.720 Then when we went to l A, we did the 0:03:53.760 --> 0:03:56.400 same thing. We replicated that style in Los Angeles and 0:03:56.760 --> 0:04:00.240 long the upshot of this all is we end up 0:04:00.320 --> 0:04:06.840 in a indoor uh skydiving facility having a conversation like 0:04:06.920 --> 0:04:09.040 you know, a normal conversation or trying to That was 0:04:09.120 --> 0:04:12.160 the gig, the gig. That was the gag. That was 0:04:12.200 --> 0:04:15.800 the bit. Yeah, and you get slung against the side 0:04:15.800 --> 0:04:16.880 of it at the end, which is kind of the 0:04:16.880 --> 0:04:20.040 funniest part. Yeah, it really really was. It was supposed 0:04:20.040 --> 0:04:22.120 to be an outtake and they made it an intake. 0:04:22.680 --> 0:04:25.600 Those things were very difficult to uh if you've never 0:04:25.640 --> 0:04:28.000 done one before. There, I mean, it was fun and 0:04:28.080 --> 0:04:31.160 kind of cool, but it's not easy. You don't just 0:04:31.240 --> 0:04:33.880 go in there and be like, hey, I'm floating. No, 0:04:34.040 --> 0:04:36.880 it's really really hard actually, yeah, like you're working every 0:04:36.920 --> 0:04:38.960 muscle in your body. It's kind of like water skiing 0:04:39.000 --> 0:04:41.160 looks fun too. Yeah you were good at it. I 0:04:41.240 --> 0:04:43.400 was not very good. I was okay, but it was 0:04:43.480 --> 0:04:47.279 it was tough. Yeah. So, um, that was what would 0:04:47.279 --> 0:04:50.640 be technically called a vertical wind tunnel, right, And they 0:04:50.640 --> 0:04:55.560 actually used those two to research spin. Um, Like, when 0:04:55.640 --> 0:04:59.120 something goes in, uh, like a tail spin, like a 0:04:59.160 --> 0:05:02.000 helicopter goes in a tailspin, they would use a vertical 0:05:02.080 --> 0:05:05.120 wind tunnel to test for that kind of thing. Right. 0:05:05.200 --> 0:05:06.800 But the wind tunnels we kind of more think of 0:05:06.839 --> 0:05:10.240 are the horizontal tubes where you see a car or 0:05:10.279 --> 0:05:12.560 something like that having the cool smoke blown over it 0:05:12.600 --> 0:05:16.240 for a commercial. But they're very useful. Um, and this 0:05:16.320 --> 0:05:18.240 is something I didn't really know I kind of I 0:05:18.320 --> 0:05:19.960 kind of just thought they were all these big giant 0:05:20.000 --> 0:05:22.599 things that you would put an actual car in. Most 0:05:22.640 --> 0:05:26.840 wind tunnels are these little desktop models that you use 0:05:26.880 --> 0:05:30.800 in a science lab that have a scale model that 0:05:30.839 --> 0:05:34.640 you're using instead of the actual thing, right, which which means, yeah, 0:05:34.680 --> 0:05:38.039 that you're using a smaller version, but that is precisely 0:05:38.240 --> 0:05:43.920 scaled down. It looks the right size, doesn't quit. I'm 0:05:43.920 --> 0:05:46.320 sure this plane will fly, this is close enough. But 0:05:46.440 --> 0:05:48.520 what's neat about that is that they can scale this 0:05:48.680 --> 0:05:50.920 thing down. They can subject it to, you know, the 0:05:51.200 --> 0:05:53.640 same conditions as they would a full size model. But 0:05:53.720 --> 0:05:56.799 then they can correct for the data for that whatever 0:05:56.920 --> 0:05:59.839 with the numbers they're getting the output, they can correct 0:06:00.279 --> 0:06:04.080 to scale it back upwards. Um, just using math. Because 0:06:04.360 --> 0:06:06.120 if there's one thing that goes hand in hand with 0:06:06.160 --> 0:06:09.440 wind tunnels, it is math, friends, Because the whole point 0:06:09.440 --> 0:06:12.480 of wind tunnels is to study aerodynamics, which is the 0:06:12.480 --> 0:06:15.719 flow of air or gas is over an object. Um 0:06:16.000 --> 0:06:18.080 And in this case it's a stationary object and the 0:06:18.120 --> 0:06:20.920 wind is moving. But what they're really doing is simulating 0:06:21.279 --> 0:06:24.440 that object moving out there in the real world into wind. 0:06:24.920 --> 0:06:27.200 And I mean, that's a wind tunnel. And when you 0:06:27.240 --> 0:06:29.520 put it like that, it sounds very simple. They are 0:06:29.560 --> 0:06:33.080 not simple at all. There's really nothing about wind tunnels 0:06:33.120 --> 0:06:36.680 that's simple, from their construction, to their cost, to what 0:06:36.839 --> 0:06:40.080 they're used for, to all of the different variables and 0:06:40.120 --> 0:06:43.920 conditions that they can test for there they grew step 0:06:44.080 --> 0:06:47.200 in step, hand in hand with the aviation industry, Like 0:06:47.240 --> 0:06:49.960 we probably wouldn't have an aviation industry right now without 0:06:49.960 --> 0:06:54.000 wind tunnels. Um and that should kind of give you 0:06:54.040 --> 0:06:57.480 an idea of how complex the stuff that people are 0:06:57.480 --> 0:07:00.800 doing in wind tunnels is, or the data they're extracting 0:07:00.839 --> 0:07:03.760 from these wind tunnels tests. It's not just like, look 0:07:03.839 --> 0:07:07.200 that cool green smoke bending over the car. That's for 0:07:07.200 --> 0:07:11.560 for yokels like you and I watching ads while you know, 0:07:12.040 --> 0:07:15.440 in between golf, you know, like you're watching golf and 0:07:15.480 --> 0:07:19.120 the ad comes on my brain. Is the best part 0:07:19.120 --> 0:07:23.880 of golf, The ads I've actually kind of gotten. Are 0:07:23.920 --> 0:07:26.520 you watching golf now? Yeah? Kind of here there. It's 0:07:26.520 --> 0:07:28.720 not something I seek out. But and it's not for 0:07:28.760 --> 0:07:30.640 the golf. I could care less about the golf. It's 0:07:30.680 --> 0:07:33.840 the it's the views, it's the shots. The golf courses 0:07:33.840 --> 0:07:37.320 are just they have the most amazing backdrops and it's 0:07:37.360 --> 0:07:40.640 just so tranquil and calm. It's really something. Yeah, you know, 0:07:40.680 --> 0:07:43.080 I live right down the street from the legendary East 0:07:43.160 --> 0:07:48.560 Lake Country Club in Atlanta, Bobby Jones Course, and been 0:07:49.440 --> 0:07:51.720 to one day of that one tournament. That's the only 0:07:51.720 --> 0:07:55.480 time I've actually been to a professional golf tournament and 0:07:55.560 --> 0:07:58.200 you know, I stood there twelve feet from Tiger Woods 0:07:58.200 --> 0:08:01.600 and the tea box is pretty pretty neat. Wow, like 0:08:01.680 --> 0:08:04.240 just to see because I played golf a lot growing 0:08:04.320 --> 0:08:07.559 up and it's a hard sport and to see someone 0:08:07.600 --> 0:08:11.200 do it uher perfectly right in front of your face 0:08:11.640 --> 0:08:13.920 with that much power, was it was. It was really impressive. 0:08:14.200 --> 0:08:17.240 You know what, what would really help Tiger Woods swing 0:08:17.560 --> 0:08:19.680 if they put him in a wind tunnel, put some 0:08:19.800 --> 0:08:22.520 green smoke in the wind and watch them swing. They 0:08:22.520 --> 0:08:24.480 could tell him how to do it better. You want 0:08:24.520 --> 0:08:28.200 smoke him smoke that's right, that's right. Shout out to 0:08:28.280 --> 0:08:31.960 our Guard Detroit crew from the day. Al Right, So 0:08:32.200 --> 0:08:33.960 if you want to go back in time and talk 0:08:33.960 --> 0:08:37.560 about human flight, you're gonna look at things like Da 0:08:37.640 --> 0:08:45.120 Vinci's ornithopter and kind of a lot of early stabs 0:08:45.240 --> 0:08:50.920 at flying were humans looking at birds and thinking, well, 0:08:50.960 --> 0:08:53.240 if we're gonna fly, we're gonna have to learn how 0:08:53.280 --> 0:08:57.120 to flap wings really fast. And it made sense. I 0:08:57.120 --> 0:08:59.040 guess if you're looking at birds, they're the only thing 0:08:59.080 --> 0:09:02.240 flying around. Uh, it would make sense that that's where 0:09:02.280 --> 0:09:05.000 they would go. But they knew early on, regardless of 0:09:05.040 --> 0:09:10.040 the flapping, that they needed to understand wind and how 0:09:10.120 --> 0:09:13.920 wind worked with wings. And so they started going to 0:09:14.760 --> 0:09:17.120 these little hills and mountains and they started going to 0:09:17.200 --> 0:09:20.320 caves that had you know, they were looking for some 0:09:20.400 --> 0:09:23.440 sort of predictable, constant wind so they could do some 0:09:23.520 --> 0:09:27.280 early testing. And they realized, you just can't do it 0:09:27.320 --> 0:09:30.400 with mother nature. You can't get a consistent wind, not 0:09:30.640 --> 0:09:33.319 enough to get real data out of it and do 0:09:33.400 --> 0:09:36.520 that math that we need so so drastically to make 0:09:36.559 --> 0:09:39.880 this possible. Right so, and and initially we got that 0:09:39.920 --> 0:09:42.560 assist from birds and that we knew wings had to 0:09:42.600 --> 0:09:45.640 be involved. That the whole flapping thing really kind of 0:09:45.679 --> 0:09:48.200 threw things off for a while. But because we knew 0:09:48.240 --> 0:09:50.439 that there had to be wings, we knew that there 0:09:50.480 --> 0:09:55.079 had to probably be some ideal or optimum shape of wings. 0:09:55.520 --> 0:09:58.000 And that's really where wind tunnels first got their start, 0:09:58.360 --> 0:10:01.760 wasn't testing different shape of wings or air foils. And 0:10:01.800 --> 0:10:04.360 there was a guy back in seventeen forty six named 0:10:04.360 --> 0:10:09.880 Benjamin Robbins who created a wiry arm um, which is 0:10:09.920 --> 0:10:14.920 basically like a It was a centrifuge basically is what 0:10:15.040 --> 0:10:17.440 he created. He had a hard time picturing this, and 0:10:17.480 --> 0:10:21.520 there's only there's this one very rudimentary sketch that made 0:10:21.520 --> 0:10:24.720 it even more confusing. Okay, so just just imagine you 0:10:24.760 --> 0:10:28.640 have like a pole coming out of the ground vertically 0:10:29.280 --> 0:10:31.480 and you have an arm attached to that pole, and 0:10:31.520 --> 0:10:34.360 the pole can spin around in a circle like a centrifuge, 0:10:34.440 --> 0:10:37.640 like one of those G force testers that they have 0:10:37.840 --> 0:10:40.880 at and like, um, like astronaut training, you know what 0:10:40.920 --> 0:10:44.680 I'm saying. Yeah, yeah, yeah, that thing. This is what 0:10:44.760 --> 0:10:47.439 that guy invented. But it was like with wood and 0:10:47.280 --> 0:10:49.880 in the dirt. It wasn't and it didn't go that fast. 0:10:50.160 --> 0:10:53.560 But you could have fixed a like a wing type 0:10:53.600 --> 0:10:55.679 that you were testing to see if it worked well 0:10:55.960 --> 0:10:58.120 to the end of it and push it through the air. 0:10:58.559 --> 0:11:01.360 And it didn't really help this guy figure out what 0:11:01.440 --> 0:11:05.080 wings style or size was the best. What it helped 0:11:05.120 --> 0:11:07.800 him figure out is that it doesn't have that much 0:11:07.880 --> 0:11:10.160 to do with anything with flapping. We don't need to 0:11:10.160 --> 0:11:14.400 be wasting our time inventing machines that that flap their wings, 0:11:14.440 --> 0:11:16.920 because that's not it. It's all about this thing called 0:11:17.000 --> 0:11:20.960 lift and drag and the proportion between those two. And 0:11:21.000 --> 0:11:23.040 if you can figure out how to get more lift 0:11:23.080 --> 0:11:26.920 and decreased drag. Then you can you can really make 0:11:26.960 --> 0:11:30.120 some you can fly basically, And this was the very 0:11:30.240 --> 0:11:34.520 first inklings of that that Benjamin Robbins came came up with. Yeah, 0:11:34.520 --> 0:11:36.360 and what I saw was that Robbin's really kind of 0:11:36.360 --> 0:11:40.319 pinpointed drag, like the shape is super important. And then 0:11:40.400 --> 0:11:44.160 after him, Sir George Cayley had his own whirling arm 0:11:44.240 --> 0:11:46.520 and he's the one that really figured out lift was 0:11:46.960 --> 0:11:50.120 a key. After they realized the shape of the thing 0:11:50.200 --> 0:11:53.560 matters the um more than the shape, like the size 0:11:53.600 --> 0:11:57.559 of it matters. Size does matter, especially when you're flying, 0:11:57.679 --> 0:12:01.200 especially when you're flying, and uh that if you could 0:12:01.240 --> 0:12:04.320 just get a quick enough takeoff, you don't need to 0:12:04.320 --> 0:12:06.320 flap at all. All you need is a lot of 0:12:06.360 --> 0:12:10.360 speed at first, which they could have also gotten frankly 0:12:10.400 --> 0:12:13.160 by if they would have kept looking at birds and 0:12:13.200 --> 0:12:16.520 realized they eventually stopped flapping, they might have realized, oh, 0:12:16.600 --> 0:12:18.280 you actually don't need to flap the whole time. You 0:12:18.280 --> 0:12:21.240 can glide if you've got enough speed, right and and well, 0:12:21.280 --> 0:12:24.240 actually a lot of the early flying machines were gliders. 0:12:24.280 --> 0:12:26.560 It was one of the the Wright brothers were not 0:12:26.600 --> 0:12:30.640 the first people to UM engage in in human flight. 0:12:31.040 --> 0:12:34.800 There is a monk named Elmer of Malmsberry who has 0:12:34.880 --> 0:12:38.040 the first recorded human flight back in ten fifty c 0:12:38.280 --> 0:12:42.200 E not b C and um he he You know, 0:12:42.360 --> 0:12:46.880 that was almost a thousand years before the Right Brothers UM. 0:12:47.040 --> 0:12:50.080 But the Right Brothers are credited with with UM the 0:12:50.320 --> 0:12:54.560 like an engine powered flight human flight. Right, So they 0:12:54.600 --> 0:12:58.240 they were dabbling in what's what Kaylee and Robbin's well, 0:12:58.320 --> 0:13:01.320 Kaylee especially figured out that you need thrust and there's 0:13:01.360 --> 0:13:04.160 just nothing around that's light enough to produce enough thrust. 0:13:04.480 --> 0:13:07.520 So Kaylee actually gave up and went and joined parliament 0:13:07.520 --> 0:13:10.440 for a while before he finally created a flying machine. 0:13:10.440 --> 0:13:14.600 Fifty years before the Right Brothers. He made his UM. 0:13:14.640 --> 0:13:18.040 He made his coach driver test pilot it, and the 0:13:18.120 --> 0:13:20.599 coach driver was so scared even though the flight was 0:13:20.640 --> 0:13:22.959 successful that when he landed he was like, I quit, 0:13:23.000 --> 0:13:26.280 I quit. I'm not. I don't work for you anymore. Yeah, 0:13:26.559 --> 0:13:30.360 but George Kayley's very much overlooked figure in the history 0:13:30.360 --> 0:13:34.840 of flight. He apparently figured out the general shape um 0:13:34.840 --> 0:13:39.719 of a modern airliner back in Yeah. Alright, I say 0:13:39.760 --> 0:13:42.480 we take a break, we'll come back and talk about 0:13:42.520 --> 0:14:10.920 the first wind tunnel right after this. Alright, so Kaylee 0:14:10.960 --> 0:14:16.079 has these whirling arms going terrible name, but it worked out. Uh. 0:14:16.080 --> 0:14:19.400 Then enter a man named Frank h Win him. He 0:14:19.440 --> 0:14:21.960 was another Englishman and he was in the Aeronautical Society 0:14:21.960 --> 0:14:25.480 of Great Britain, and he said, guys, we need or 0:14:25.480 --> 0:14:29.200 excuse me, gentlemen, we need a wind tunnel, and we 0:14:29.240 --> 0:14:32.240 need it bad. And so in eighteen seventy one he 0:14:32.320 --> 0:14:35.360 had the very first wind tunnel. Was twelve ft long, 0:14:35.920 --> 0:14:39.920 about eighteen inches square, with a forty mile wind, which 0:14:39.920 --> 0:14:43.280 is pretty good. It was. It consisted of your daughter going, 0:14:43.800 --> 0:14:47.760 oh god, stinky has went dunne her breath. Isn't that 0:14:47.800 --> 0:14:50.720 stinky yet? Kids don't really start to stink until later, 0:14:50.760 --> 0:14:56.320 I think, yeah, until later. But the winds were powered 0:14:56.360 --> 0:14:59.240 by a steam fan at the end of the tunnel, 0:15:00.120 --> 0:15:02.760 and it worked pretty well. He was able to get 0:15:02.800 --> 0:15:05.800 that leading edge of the airfoil and move it up 0:15:05.840 --> 0:15:09.000 and down and change his angle angle of attack and 0:15:09.320 --> 0:15:12.120 kind of see what shaped, uh and what angles worked 0:15:12.160 --> 0:15:15.440 best with to get the best lift. But it was 0:15:15.480 --> 0:15:18.760 still sort of choppy, and it was rough around the edges. 0:15:18.880 --> 0:15:21.320 And if you really want to make this you know, 0:15:21.360 --> 0:15:24.440 if you want to fly safely, you got to have 0:15:24.480 --> 0:15:28.920 a really really really consistent, very smooth wind to work 0:15:28.960 --> 0:15:30.840 with to get that data. And they still didn't have 0:15:30.880 --> 0:15:33.040 one at this point. Now they still didn't, but they 0:15:33.080 --> 0:15:35.800 were advancing by leaps and bounds here that people were 0:15:35.840 --> 0:15:39.440 building their own wind tunnels. Because up to that point, 0:15:39.800 --> 0:15:42.400 if you had in a design for an airfoil, for 0:15:42.480 --> 0:15:45.400 like a wing size or shape, you had to build 0:15:45.440 --> 0:15:47.040 it and then go take it out into nature and 0:15:47.080 --> 0:15:49.040 test it and hope for the best, and it was 0:15:49.160 --> 0:15:52.720 really expensive, really time time consuming. With your own wind 0:15:52.760 --> 0:15:54.920 wind tunnel, you could make a model of the shape 0:15:54.920 --> 0:15:58.000 and test it out yourself and then see this is 0:15:58.000 --> 0:16:01.320 actually worth pursuing, or this as junk, and that's it. 0:16:01.440 --> 0:16:04.880 That's what our dear beloved heroes, the Right brothers did 0:16:04.960 --> 0:16:09.320 in Ohio outside of Dayton, Lorville and Wilbur Wright Um 0:16:09.520 --> 0:16:13.640 built their own wind tunnel. These guys were just like tinkerers. 0:16:13.640 --> 0:16:16.440 They owned a bike shop, but they were so fascinating 0:16:16.520 --> 0:16:19.200 were following these developments in early flight that they just 0:16:19.280 --> 0:16:21.520 kind of got into it themselves and they built themselves 0:16:21.520 --> 0:16:24.120 a wind tunnel. They had like two different or two 0:16:24.200 --> 0:16:27.080 hundred different types of wings. I believe that they messed 0:16:27.080 --> 0:16:30.480 with selected the thirty best ones that they had developed 0:16:30.480 --> 0:16:33.040 in their wind wind tunnel of their own construction and 0:16:33.080 --> 0:16:38.680 design um And apparently I saw somewhere that by nine one, 0:16:38.720 --> 0:16:41.600 after their wind tunnel tests, the Right Brothers, a couple 0:16:41.640 --> 0:16:46.440 of bicycle repairment in Dayton, had the world's um most 0:16:46.560 --> 0:16:53.080 accurate data scientific data on on flying and wings in 0:16:53.120 --> 0:16:56.800 the world. And they'd come up with it entirely by themselves. Yeah, 0:16:56.880 --> 0:16:59.200 and here's the thing with these wind tunnels, especially early 0:16:59.280 --> 0:17:02.440 on in kind of still, it's not like they could 0:17:02.520 --> 0:17:04.600 use that wind tunnel and come out with a surefire 0:17:04.640 --> 0:17:08.960 product using math and uh and testing different designs and 0:17:09.040 --> 0:17:12.159 shapes and tilts and angles. But it was such a 0:17:12.200 --> 0:17:16.760 time saver and broken bone saver that you didn't just say, 0:17:16.920 --> 0:17:18.600 all right, well, I think this might work. Let's go 0:17:18.680 --> 0:17:21.439 and push our cousin off of a cliff or our 0:17:22.080 --> 0:17:24.880 coach driver or whatever and see if it works. They 0:17:24.920 --> 0:17:27.960 still had their failures, all of them did, But I 0:17:28.000 --> 0:17:30.360 mean it would have taken I mean, god knows how 0:17:30.359 --> 0:17:33.720 many more years if they didn't, like at least start 0:17:33.760 --> 0:17:37.480 from a point of likely success thanks to wind tunnels. 0:17:37.680 --> 0:17:39.400 But I mean, like, look at it. They went from 0:17:39.560 --> 0:17:42.560 they finished their wind tunnel tests in nineteen o one, 0:17:42.920 --> 0:17:45.920 they had their first powered flight in en three. Yeah, 0:17:46.000 --> 0:17:48.199 I mean that's so it's amazing two years and it 0:17:48.240 --> 0:17:51.480 definitely did accelerate it too. And so you can see 0:17:51.520 --> 0:17:55.240 from the outset that that aviation and wind tunnels just 0:17:55.320 --> 0:18:00.720 developed together, and wind tunnels developed aviation um. But the 0:18:00.720 --> 0:18:02.600 first wind tunnels, like you said, they had a really 0:18:02.600 --> 0:18:06.520 big problem, and that was the air that they produced. 0:18:06.560 --> 0:18:11.159 The stream of wind was very choppy, very turbulent, and 0:18:11.480 --> 0:18:15.440 your data was not necessarily reliable. It wasn't too terribly 0:18:15.520 --> 0:18:18.159 much better than say, going out into mother Nature and 0:18:18.240 --> 0:18:22.719 subjecting you know, the same model to those winds um 0:18:22.920 --> 0:18:25.359 And that's a big problem. So one of the first 0:18:25.400 --> 0:18:28.240 things that they figured out how to do was to 0:18:28.560 --> 0:18:32.920 make the wind smoother so that you could get a reliable, smooth, 0:18:33.000 --> 0:18:37.320 steady wind um in your wind tunnel whenever you wanted 0:18:37.359 --> 0:18:39.639 to use it. Yeah, and that's where we come to 0:18:39.760 --> 0:18:43.639 the modern tunnel, very very smooth airflow. And they have 0:18:44.440 --> 0:18:48.119 five basic sections of and they're you know, they're all different, 0:18:48.160 --> 0:18:50.760 but they have five basic sections. In a modern tunnel 0:18:51.640 --> 0:18:55.240 that's the settling chamber, the contraction cone, the test section, 0:18:55.280 --> 0:18:59.840 the diffuser, and the drive section. So we start out 0:18:59.840 --> 0:19:02.639 with this swirling air and it's a big choppy mess 0:19:03.160 --> 0:19:05.320 and it enters the tunnel and we'll talk about how 0:19:05.359 --> 0:19:08.200 in a second, because it's kind of cool, little counterintuitive, 0:19:08.240 --> 0:19:10.600 but it makes a lot of sense. Um it goes 0:19:10.600 --> 0:19:13.880 into the settling chamber, which does exactly what you think. 0:19:13.920 --> 0:19:16.760 It settles that air, straightens it out. They might have 0:19:16.800 --> 0:19:20.680 these little honeycomb holes or a screen or these panels, 0:19:21.119 --> 0:19:22.960 and that's just sort of the initial thing to sort 0:19:23.000 --> 0:19:25.119 of get it nice and smooth and moving in the 0:19:25.160 --> 0:19:28.439 same uniform direction. Yeah, and then it goes down. They 0:19:28.480 --> 0:19:31.760 step it down through that contraction cone, and that just 0:19:32.040 --> 0:19:35.040 I mean, it's like anything else. If you make the 0:19:35.040 --> 0:19:38.919 the tube smaller, it's going to increase that velocity of 0:19:39.000 --> 0:19:42.760 air flow. And that's where it gets to the test section, 0:19:42.800 --> 0:19:45.240 which is whatever. And the test section depends on what 0:19:45.240 --> 0:19:48.119 you're testing. If it's a desktop thing, the test section 0:19:48.240 --> 0:19:51.919 might be twelve inches long and you might have a 0:19:51.920 --> 0:19:55.480 tiny little model of an airplane wing in there, and 0:19:55.520 --> 0:19:57.600 that's where the actual thing you're testing is and where 0:19:58.040 --> 0:20:02.280 all the sensors are record all the data because you know, 0:20:02.440 --> 0:20:04.280 you've got your visual that you've got these windows so 0:20:04.320 --> 0:20:06.439 you can shoot TV commercials and you can look at 0:20:06.480 --> 0:20:09.919 the thing. But there's also all manner of sensors to 0:20:10.000 --> 0:20:14.200 pick up on all manner of UH data and observations. Yeah, 0:20:14.280 --> 0:20:16.280 I think that's really cool that they still you know, 0:20:16.359 --> 0:20:19.119 when they operate wind tunnels, they still watch through the 0:20:19.160 --> 0:20:22.720 window because there's a lot to be gained visually from 0:20:22.800 --> 0:20:25.919 from just human beings watching this stuff, and so you 0:20:25.920 --> 0:20:28.600 want to you want to watch it right, Yeah, for sure, 0:20:28.680 --> 0:20:31.360 especially when they got the green smoke thing turned on. 0:20:33.119 --> 0:20:36.359 So after it goes through the um, the test section 0:20:36.840 --> 0:20:40.960 enters a diffuser UM which kind of it slows things, 0:20:41.560 --> 0:20:44.960 slows things down UM and maybe just exits the whole thing. 0:20:45.119 --> 0:20:47.080 It's kind of the opposite of the contractor it just 0:20:47.160 --> 0:20:51.560 opens back up right exactly. So there's UM, there's there 0:20:51.800 --> 0:20:55.240 as far as breaking. There's a lot of different kinds 0:20:55.320 --> 0:20:58.440 of wind tunnels, as we'll see, but there's really kind 0:20:58.480 --> 0:21:01.760 of two categories too, broad categories. You've got open and 0:21:01.880 --> 0:21:05.040 closed circuit, and an open circuit is where you have 0:21:05.640 --> 0:21:08.200 wind going in on one end, going through the diffuser 0:21:08.200 --> 0:21:09.800 and the honeycomb in the test section and then coming 0:21:09.800 --> 0:21:13.600 out the other end blowing into the room and another 0:21:14.080 --> 0:21:16.879 with the closed circuit. It's just basically an oval and 0:21:16.920 --> 0:21:20.119 so when the wind is generated, it goes through the 0:21:20.280 --> 0:21:22.320 it goes through the test section out the back, but 0:21:22.359 --> 0:21:25.160 then bends around an oval track and then comes back 0:21:25.200 --> 0:21:28.120 around again and through the contraction coning into the test 0:21:28.119 --> 0:21:31.000 section again and again, and can just keep going rather 0:21:31.040 --> 0:21:33.960 than just blowing out the other side. Yeah, and here's 0:21:33.960 --> 0:21:36.200 the part that I said wasn't intuitive, but it's really 0:21:36.280 --> 0:21:38.879 kind of neat when you think about it. The drive 0:21:38.960 --> 0:21:41.680 section is where this fan is, and this is what 0:21:41.840 --> 0:21:45.800 it's just generating that air flow. And I always just 0:21:45.840 --> 0:21:48.520 thought a wind tunnel was a fan pointing at the thing. 0:21:49.440 --> 0:21:53.119 They're actually behind the thing, because you don't want to 0:21:53.200 --> 0:21:57.560 push air onto something, you want air being pulled over something. 0:21:57.680 --> 0:22:00.119 And it it just makes total sense, but you ever 0:22:00.160 --> 0:22:02.359 really thought about it, You just I always just pictured 0:22:02.400 --> 0:22:05.200 a big fan blowing at a car, but the fan 0:22:05.240 --> 0:22:07.760 would actually be behind the car and it's probably looping 0:22:07.800 --> 0:22:11.320 around and smoothing out this entire way and then being 0:22:11.359 --> 0:22:14.399 gently pulled over the car exactly. And in just the 0:22:14.440 --> 0:22:17.880 same way that the fastest way to cool off, say 0:22:17.920 --> 0:22:21.439