WEBVTT 1 00:00:06.790 --> 00:00:14.200 Mark Kushner: The Fourteenth Annual Symposium. This is the 2 00:00:14.270 --> 00:00:27.899 Mark Kushner: opportunities for our graduate students, both here at University of Michigan, Michigan State University in Toledo, Notre Dame, who, their research results, do something networking 3 00:00:27.980 --> 00:00:30.130 Mark Kushner: and learn from each other. 4 00:00:30.530 --> 00:00:37.580 Mark Kushner: Symposium. We have a seminar speaker 5 00:00:37.610 --> 00:00:52.610 Mark Kushner: Collins from Oakridge National Laboratory, who will be introduced just in a few moments prior to that introduction. I'd like to introduce. Go to 2 ton. Quote 6 00:00:53.350 --> 00:00:55.410 Mark Kushner: good 7 00:00:55.480 --> 00:01:02.799 Mark Kushner: from Wednesday University. Who will give us a few words about the Avs. Michigan chapter 8 00:01:23.730 --> 00:01:25.720 Mark Kushner: presentation. 9 00:01:25.860 --> 00:01:44.419 Mark Kushner: Hello, yeah. Hello, everyone. Thanks for the we are happy to collaborate with Michigan is plasma science and engineering to contribute this 10 00:01:44.420 --> 00:02:05.509 Mark Kushner: American Vacuum Society, avs, Michigan. Chapter talk about our spring symposium and our newly founded Avs. Branch here at University of Michigan. My name is ages. I'm an assistant professor at Wayne State University, and I'm the current chair of at Michigan chapter 11 00:02:06.890 --> 00:02:30.189 Mark Kushner: familiar with Abs. But I just wanted to include an slide here to the international community of scientists, engineers, and manufacturers interested in looking technologies. The topics we are interested in covered a wide range from surface technology, the vacuum engineering the position 12 00:02:30.570 --> 00:02:53.279 Mark Kushner: scientific journals that you can publish your research and annual international symposium. It's been organized. And the goal of abs in general is to Foster international collaborates, collaboration and build. And it's an inclusive society in Michigan. We are. And 13 00:02:53.640 --> 00:03:15.850 Mark Kushner: we have me 14 00:03:15.850 --> 00:03:35.929 Mark Kushner: Michigan State University. We have a couple of activities going on over the years the most kind of the one I'd like to talk about today is spring simple zoom. We had it last year at University of Michigan, and the team was 15 00:03:36.010 --> 00:04:05.709 Mark Kushner: 10 films and plasma for future micro electronics. And this year we will hold it at Wayne State university, and the team will be noble computing paradigms the date will be in zoom, and more information will follow. But you can reach out to me if you'd like to hear more about it. I included each of the slides. They direct you to the Avs. Michigan chapters website. And my email address 16 00:04:06.190 --> 00:04:22.369 Mark Kushner: from last year's symposium. I hope we will see students participating in the Abs. Michigan chapter as well. Lastly, the 17 00:04:40.030 --> 00:05:00.480 Mark Kushner: University of Michigan and being involved with with this student chapter can you like networking opportunities, career development opportunities. And it will be a like nice pro platform research and education is related to the 18 00:05:00.480 --> 00:05:23.590 Mark Kushner: thanks again for amazing. 19 00:05:23.700 --> 00:05:25.390 Thank you. Program 20 00:05:51.600 --> 00:05:52.590 Mark Kushner: pressure. 21 00:05:53.620 --> 00:05:54.760 Mark Kushner: Some phone 22 00:06:00.520 --> 00:06:17.910 Mark Kushner: astrophysics. 23 00:06:18.460 --> 00:06:32.630 Mark Kushner: University of California, Irvine, Vd. National Fusion facility became a star scientist at General Atomic in 22,016, 24 00:06:33.320 --> 00:06:38.800 Mark Kushner: specialized in spectroscopy, diagnostics, and energetic department physics. 25 00:06:38.940 --> 00:07:07.170 Mark Kushner: and joined our now in 2020 and driven by a long time passion for success, of fusion, energy. She has served in multiple outreach and strategic planning activities, including the Ap community planning process and the USB special seminar that we've got. 26 00:07:07.170 --> 00:07:25.819 Mark Kushner: How many have we given out now? Marks? It can't be. It must be more than Nobel prizes now, but career awards winner for 2,023. So we have this nice part. 27 00:07:25.950 --> 00:07:29.519 Mark Kushner: We just can. We have you guys? 28 00:08:03.420 --> 00:08:06.330 Mark Kushner: But we I heard it. 29 00:08:12.510 --> 00:08:24.340 Mark Kushner: Okay. And then maybe one of the 30 00:08:46.840 --> 00:08:51.579 Mark Kushner: a little bit. Okay, here we go. Thank thank you. Everyone very excited to be here. 31 00:08:52.020 --> 00:09:07.160 Mark Kushner: Thanks. So much for the introduction. And I'm gonna talk about integrating physics and engineering for fusion reactor design, assessment and optimization. So that was a great introduction. And here it is in pictures. II just wanted to 32 00:09:07.290 --> 00:09:15.409 Mark Kushner: kind of everybody's path in whatever field you're in is different. This was mine. I actually got interested in fusion in fifth grade. 33 00:09:15.410 --> 00:09:37.530 Mark Kushner: and thought it was something I wanted to do, and I went to undergrad in state in Montana, where they didn't have fusion research per se. But II did a little bit of materials, research in solid oxide fuel cells and and in solar physics. And one of the things that helped me sort of go was to apply for fellowships, and I would I, at the time it was 34 00:09:37.760 --> 00:10:01.790 Mark Kushner: called national Undergraduate Fellowship, but it's now it's called Suli for for undergrads. Between my my junior and senior year, I went to the summer project at D. It was a total disaster. It was a simulation project didn't work out, but I still wanted to do fusion after that. And I wanted. I went to Wisconsin, and it was really neat because I got to build an entire experiment from scratch. When I showed up I said I wanted to do fusion, energy research. And 35 00:10:01.790 --> 00:10:14.500 Mark Kushner: they said, we have a perfect unmagnetized plasma for you to build in laboratory astrophysics, but same equations and a lot very useful experience as an experimentalist. 36 00:10:14.500 --> 00:10:23.390 Mark Kushner: And so then, once II actually was like, I really want to do fusion. And made a connection to go to, to 37 00:10:23.480 --> 00:10:41.660 Mark Kushner: how much lingo and how many acronyms. And it's a totally different language. And it was very overwhelming. And I was like, Wow, fusion is really hard. And and then I kinda after some of the experiences that at this point my goal in life is to help design a fusion pilot plant. 38 00:10:41.680 --> 00:10:44.310 Mark Kushner: And this is where I met right now, and in Oak Ridge, and 39 00:10:44.400 --> 00:10:59.400 Mark Kushner: one of the major impacts in my career has been the recent history of fusion. So I think it's important to to talk about this because, the community, the entire Fusion community, came together in a series of workshops 40 00:10:59.730 --> 00:11:25.140 Mark Kushner: and several reports came out from beginning with the National Academies in 2,018, and they said, Hey, we've advanced a lot. Let's make a fusion pilot plant by the twenty-fourties. And then the community planning workshops came in to say, this is what we need to do to get there. After that there was a fisac report that they're able to advise DOE, and they said, Hey, do what the community plan said. But here's how much it costs. 41 00:11:25.140 --> 00:11:51.970 Mark Kushner: And then, after that, there were further studies from the National Academies in 2021, bringing fusion to the Us. Grid. So they they used the informed by industry. We need to get a design by 2028, and electricity by 2,035 to be impactful. And then from there the the Department of Energy has released a milestone program for private industry to participate and basically prove their concepts 42 00:11:52.030 --> 00:12:01.010 Mark Kushner: in a milestone type approach. And then we actually recently had a Us eater research program workshop where we talked about what we would do with heater. So 43 00:12:01.460 --> 00:12:21.759 Mark Kushner: all of this led me actually to Oakridge. I joined Oakridge because of the potential to execute the the community plan, and and our vision there is that fusion. Energy will be an electricity source for this generation. The this was sort of a picture of our fusion energy division. I'm actually interim 44 00:12:21.780 --> 00:12:45.390 Mark Kushner: section head of the burning plasma side. We also have fusion, nuclear science, technology and engineering. You can see some of these groups are all of them almost map directly to pieces of the community plan. And the lab is also really big. It's actually twice the size of my hometown. So there's lots of science that happens there, including many things that are important for fusion, such as material science, advanced manufacturing 45 00:12:45.390 --> 00:12:53.009 Mark Kushner: half my team that I'm currently working with on research is from vision, and and there's the fastest supercomputer in the world. 46 00:12:53.010 --> 00:12:58.780 Mark Kushner: I don't care so really trying to bring together all of these things is very exciting to work. 47 00:12:58.830 --> 00:13:18.910 Mark Kushner: So today, I'm gonna talk about the motivation for magnetic fusion energy and then talk about some of the challenges and frontiers in developing fusion energy. So the first will be on going into burning plasma and a little bit of fast sign physics. That's a little bit of my specialty but mostly focusing on the Tokomat concept. 48 00:13:18.910 --> 00:13:33.859 Mark Kushner: And then from there a little bit about handling reactor conditions and capturing the energy from fusion, energy, and then going in a little bit about some progress that we've made in enabling more rapid fusion pilot plant design. So let's go. 49 00:13:33.990 --> 00:13:52.469 Mark Kushner: I hope everyone is inspired by this. Civilization improves with energy. As people are powered, they're able to do more things. Health improves all of these things, and as the world population is growing, the need for energy is growing dramatically. If 50 00:13:52.520 --> 00:14:16.929 Mark Kushner: this, this plot shows that if we would like to maintain a global temperature rise of less than 2 degrees, then we need to be replace replacing our carbon, producing energy sources with non carbon producing sources. And we need a lot of it. So the projected needs are something like, we need 25,000 gigawatts from non Co. 2 producing sources. That's 25,000 51 00:14:17.150 --> 00:14:21.110 Mark Kushner: plants. Power plants by 2050, 52 00:14:21.130 --> 00:14:44.730 Mark Kushner: the annual global investment would need to reach something like 23 trillion cumulative. So you can see why, recently, some of the private industries have taken interest in investing in fusion energy, because even a small portion of 23 trillion is a large income. So this, this is part of the the motivation in general. So let's make a fusion pilot plant. How do we do it? 53 00:14:44.890 --> 00:14:51.830 Mark Kushner: It's basically talking about replacing the heat source to heat water 54 00:14:52.020 --> 00:15:06.929 Mark Kushner: and make steam and turn a turbine and generate electricity. So we basically know how to do everything up here. The thing that I'm going to be talking about is how to how to do, how to make this heat source fusion rather than like, say, a full burning power plant. 55 00:15:06.930 --> 00:15:25.450 Mark Kushner: So we'll be focusing today on deuterium tritium fusion. And the reason for that is it's the easiest to do. This is showing the reaction Cross section times. The total energy release. So versus the ion temperature that it takes to to make fusion happen. So you can see the curve for Dt. You get a lot more fusion reactors 56 00:15:25.450 --> 00:15:30.339 Mark Kushner: for your for, say your your ion temperature compared to some of the other fuel cycles. 57 00:15:30.340 --> 00:15:36.330 Mark Kushner: some of the other fuel cycles like Dd and Dd. Helium 3 and and Pb. 11. 58 00:15:36.330 --> 00:16:01.329 Mark Kushner: They're they can have advantages, they produce less neutrons. Neutrons are a little difficult to deal with, as we'll discuss later. It. So this reduces the requirement for neutron tolerant materials and having different fuel cycles, removes the need for tritium breeding. So tritium is something that we have to produce, and this is part of our fuel process. But one of the issues with these higher, while the main issue is that it requires much higher temperatures 59 00:16:01.330 --> 00:16:12.650 Mark Kushner: reach, reach reach decent reaction rates. So this is hard and having higher temperatures has impacts on materials as well. So we're going to be talking about Dt fusion today. 60 00:16:12.650 --> 00:16:37.139 Mark Kushner: And just to remind everyone. This is the reaction. It's deuterium and tritium coming together, making a high energy. 14 mev neutron and a helium or alpha particle. The idea is that 20% of the reaction energy comes out in the form of the alpha particle. You want to keep that energy within the plasma to keep it sustained and keep it heated. So you don't have to keep adding extra heating. This is this is the point of 61 00:16:37.140 --> 00:16:49.520 Mark Kushner: reaching a burning plasma, and then we make electricity by collecting the energy from the neutron. And it's something like, if you had 3 water bottles full of deuterium tritium water. You could produce enough 62 00:16:49.880 --> 00:16:59.170 Mark Kushner: electricity to power a small city or major city actually, for a day, and you'd make enough helium to fill something like 400 balloons sounds really nice. 63 00:16:59.200 --> 00:17:06.369 Mark Kushner: Let's do it well, how there's a lot of fusion concepts out there. This is sort of portraying 64 00:17:06.450 --> 00:17:18.650 Mark Kushner: the main grouping of, say, magnetic fusion, energy, inertial fusion, energy, and in general, as you go to the right here, it's increasing the density, the energy, density, 65 00:17:18.750 --> 00:17:24.410 Mark Kushner: plasma density, that kind of thing. So we'll be focusing on magnetic fusion energy on the side here 66 00:17:24.420 --> 00:17:45.550 Mark Kushner: and one of the main things to start with to say, well, where are we with fusion is looking at the triple product? So this is a fundamental figure of merits, quite important self sustaining fusion react. And in order to actually make electricity, we have to have fusion gain. We have to get more fusion energy out from reaction than 67 00:17:45.950 --> 00:17:53.620 Mark Kushner: it takes to put in. Sorry. I have a little connection problem here. 1 s 68 00:17:55.090 --> 00:17:55.950 free. 69 00:18:00.620 --> 00:18:02.979 Mark Kushner: Just let's finish. Just second. 70 00:18:05.800 --> 00:18:10.239 Mark Kushner: should put it on this other computer oops. 71 00:18:12.240 --> 00:18:13.470 Mark Kushner: Hold that thought. 72 00:18:15.820 --> 00:18:16.700 Mark Kushner: okay 73 00:18:21.970 --> 00:18:22.900 Mark Kushner: again. 74 00:18:25.460 --> 00:18:54.269 Mark Kushner: Okay, great. Sorry about that. So anyway. So one of the the ways to sort of see how close we are to to having a good fusion. Energy gain is to look at the triple product. So this is really, it's like, there's 3 main things you need for fusion to to happen. You have to have enough particles. So this is a measure of density. You have to have them hot enough so they can come together and fuse, and then you've got to confine them long enough so that they have a chance to actually find each other and collide. 75 00:18:54.270 --> 00:19:14.219 Mark Kushner: And so there's a number for this, and the Ntt. Can be plotted, and we can look at the progress over time of of Nttal. And so we highlight the token back here up here somewhere is queue of one, and this would be where upcoming devices like spark and eater would be. 76 00:19:14.420 --> 00:19:16.170 Mark Kushner: Okay. So here's Tokamax. 77 00:19:16.820 --> 00:19:25.230 Mark Kushner: Here's stellarators. They're catching up. And so we're gonna be talking about Tocomax mostly. But it's not just 78 00:19:25.240 --> 00:19:48.769 Mark Kushner: the triple product that's important. Because it's also we need to make electricity. And it needs to be a sustained reaction. And so this is a triple product versus duration showing Tocomax installerators. There's different colors for them. And and you can see that in general, as we want to make a longer discharge, the Ntt. Goes down. 79 00:19:48.770 --> 00:19:56.330 Mark Kushner: and if we want to meet the goals of what was released in the Nasum 21 report for making a fusion pilot plant. 80 00:19:56.330 --> 00:20:10.910 Mark Kushner: We have to have something like in phase one. We want to be making greater than 50 megawatts of electric peak electricity for more than 3 h with queue electric, greater than one with a closed fuel cycle. So we have to be making tritium 81 00:20:11.250 --> 00:20:14.649 Mark Kushner: in phase. So that's just this first point right here. 82 00:20:15.050 --> 00:20:17.759 Mark Kushner: That's the nascent 2035 poll. 83 00:20:17.940 --> 00:20:37.199 Mark Kushner: And then, after that, if you really want to make electricity for the grid. You go on to the phases like phase, 2. Of demonstrating heat, removal, material erosion, and tritium management for a year, and then phase 3 is something like really demonstrating that you can manufacture start to manufacture components for commercialization. 84 00:20:37.310 --> 00:20:39.560 Mark Kushner: So you can see we have quite a ways to go. 85 00:20:39.730 --> 00:21:08.129 Mark Kushner: And so now this brings us into the challenges and some of the frontiers in in, in fusion, energy. So I would. I would like to classify sort of the challenges into 3 big categories. The first is, of course, controlling and sustaining and predicting the high temperature, burning plasma in order to actually produce the neutrons and the heat. And then you have to find materials that can actually handle the extreme conditions of of the reactor. 86 00:21:08.310 --> 00:21:13.089 Mark Kushner: And then you have to have actually harness the fusion power and capture it, convert it 87 00:21:13.280 --> 00:21:21.180 Mark Kushner: free tritium, a a and make electricity. So we're gonna start with the more well studied area which is 88 00:21:21.230 --> 00:21:50.120 Mark Kushner: the controlling and sustaining and predicting a burden plasma. So it's it's really exciting in terms of this. We've recently had Cfs and Mit test a new high field magnet. This is very useful for confining the plasma and getting to higher conditions. In February 2022, the jet Tokamak announced a new record of producing 59 megajoules of fusion, energy so I think, in comparison to nif nif was like 3 megajoules of fusion. 89 00:21:50.120 --> 00:21:51.909 Mark Kushner: energy, and 90 00:21:52.620 --> 00:22:02.240 Mark Kushner: importantly, fusion. Energy inspired the Chloe Spring 2023 collection, and the runway was a tokamac. So I think this is making a statement. 91 00:22:02.340 --> 00:22:15.529 Mark Kushner: But really, experiments have brought us to the point where we are really progressing in predictive capabilities and and getting towards burning plasma in the public program. We've had 92 00:22:15.530 --> 00:22:39.839 Mark Kushner: well, long term experimental devices, such as D. And San Diego, where we can really test the conditions and scenarios. This is not a Dt device, but that's has an advantage, because you can make upgrades and humans can enter. There's lots of diagnostics. And you can get the physics understanding we've got private companies like cfs that are aiming to build tokamak devices like spark where they want to get et fusion with 93 00:22:39.850 --> 00:22:56.900 Mark Kushner: queue greater than one for 2 s this is planned to come online 2025. And then we also have international devices like eater, which are aiming for a queue of 10 for longer term, like 400 s. Sort of more routine operation with a burning plasma. 94 00:22:57.000 --> 00:23:11.210 Mark Kushner: And but one of the key points is that none of these devices are actually gonna operate in the exact conditions that we envision in a compact fusion pilot plant. So no matter what we have to learn and ex extrapolate from these devices. 95 00:23:11.210 --> 00:23:35.180 Mark Kushner: but we are so. The recent jet dt fusion results are are important, not just because they made a lot of fusion energy, but actually it aligned with what we predicted. So these predictions are shaded here, and the the modeling was performed before the experiment, and then the actual data points fall within the regime of the modeling. So this is promising. But in, of course, the jet dt. Fusion. This was with Q. Less than one. And so 96 00:23:35.180 --> 00:23:54.160 Mark Kushner: one of the questions is, what happens when fusion power becomes dominant. What happens? Why do we need to study a burning plasma? Well, one thing to think about when we're thinking about burning plasmas is so that the queue. Here. Fusion gain is the the fusion power divided by the heating power that goes in, and there's a certain 97 00:23:54.160 --> 00:24:23.479 Mark Kushner: hmm. You can calculate how much of that heating is from alpha particles self heating. So once you get to scientific break, even that's gonna be alpha confinement of maybe like 17%. You're you're setting. You know, you're able to confine alpha particles. So this is the point where the plasma is transitioning from an endothermic type re reaction to exothermic. And it's it's starting to burn. But once you start getting into the actual burning plasma regime, where you would want to be going towards, you know, making a reactor. 98 00:24:23.600 --> 00:24:35.209 Mark Kushner: Interesting things happen as you get more dominant alpha heating, you can get Alpha alpha effects that drive energetic particle employees. I'll talk a little bit about that later and and some other sort of nonlinear coupling effects. 99 00:24:35.220 --> 00:24:47.099 Mark Kushner: So so these are the regimes that eater and spark may begin to test. But really we're gonna be even higher in a fusion pilot. So there's so much to go and learn. And we haven't produced any of this in magnetic fusion energy. 100 00:24:47.710 --> 00:25:14.520 Mark Kushner: The. This is an example of how the presence of Alpha heating works. So in normal discharges and Tocomax nowadays, we operate them in, say, el mode, or we have a high confinement mode that we say, and as you apply power, it's pretty predictable the Nt. Or the the fusion power will go up, but once you start to enter into a burning plasma regime, the alpha particles start to keep the plasma themselves. So it actually doesn't take much 101 00:25:14.520 --> 00:25:32.229 Mark Kushner: energy to really jump up in performance. So wanna you know, increasing the plasma temperature makes more alphas and then further increases the temperature. And these types of control dynamics are what we're gonna need to be steady in burning positive devices. This is why we need them. So 102 00:25:32.360 --> 00:25:42.450 Mark Kushner: that's one thing about burning plasma is, there's still some things about tocomat plasmos in particular, that are some issues. And I'll just talk a few sort of 103 00:25:42.480 --> 00:26:07.269 Mark Kushner: over the decade of Aps Dpp conferences I've gone to. I hear all about these things all the time. So there's disruptions. These are instabilities that in certain scenarios can cause rapid loss of control. And, for example, the plasma consignment to the wall. There's edge localized modes. When we have this high confinement mode, there's edge instability. That basically rep repeatedly bursts 104 00:26:07.370 --> 00:26:20.969 Mark Kushner: lobs of plasma out to the to hit the wall, and in general, transients like this are very bad for reactors. So it's hard enough to create sort of a nice, steady state where you're have a high powered density plasma. 105 00:26:20.970 --> 00:26:38.519 Mark Kushner: and and in that situation your materials would be exposed to something like 5 20 megawatts per square meter, steady state. And if on top of that you're also adding disruptions and elms, you really get into the regimes where there's going to be melting and materials irreversible material degradation, and this can lead to 106 00:26:38.520 --> 00:26:55.320 Mark Kushner: expensive repairs and downtime. So these types of things are very bad, and we don't want to be designing reactors that would have these types of issues. There's other core confinement, things like tearing modes. These can cause localized transport and cooling of the plasma, and this can 107 00:26:55.320 --> 00:27:11.740 Mark Kushner: actually in some cases grow and lead to a disruption. And then there's other things like fast particle instability, which are electromagnetic waves that end up, disturbing the particle orbits and causing the energetic particles to redistribute. I'm gonna talk about this a little bit more. 108 00:27:11.840 --> 00:27:35.050 Mark Kushner: But in general, you can do things for the plasma to control these you can. Well, this is actually how we do it, but you can inject frozen pellets to hmm mei, mitigate some of the disruptions. You can put things like coils in the walls, and you can inject microwaves to control the current profile plasma. That kind of thing. But in general all of these systems are gonna be 109 00:27:35.050 --> 00:27:52.729 Mark Kushner: extra on a reactor, and sometimes not even really compatible with with the engineering. So let me go a little bit into fast particles fully, just because this was a little bit of my experience. In d these, when we try to create high performance, steady state type, tocomac scenarios. 110 00:27:52.760 --> 00:28:11.129 Mark Kushner: fast Ion instabilities can limit our ability to get to high performance. So this is an example of the measured neutrons from a discharge, and if you didn't have any of these instabilities, you would expect this many neutrons in the blue line. But what we actually measured is a large deficit. It's because of these modes. 111 00:28:11.130 --> 00:28:24.990 Mark Kushner: and what it means is that you end up having if you wanted to reach a high performance this is a beta, and of what? What's a ratio of the plasma pressure to the magnetic pressure? It's a way of sort of measuring performance. 112 00:28:24.990 --> 00:28:37.259 Mark Kushner: So if you have instabilities like fast Diane disabilities, and they cause transport, then you end up having to add more neutral beam power just to get to a certain performance. So this is expensive, like, you have to pay for that. 113 00:28:37.260 --> 00:28:57.509 Mark Kushner: So we've done. And it's funny this bullet point at the bottom. It took me like 2 years to do experiments to demonstrate this. But it's turned into a bullet point that says we've done experiments that have controlled Alfie Nagin modes, and we've improved Beta, N by 15. But in the end I was like, do we really want this for a reactor? And do we need to like, can we design a reactor 114 00:28:57.510 --> 00:29:26.929 Mark Kushner: to avoid aes, and that basically inspired the rest of my my career so far. But just a little bit more for the plasma physicists, if there is any out there, the way that energetic particles transport works like because so fast ions are like alpha particles, or maybe they're excited or heated by rf, heating ion cyclotron heating. There's populations of very fast particles in the plasma, and and there's also the thermal plasma sort of the lower energy. 10 keb ranged 115 00:29:27.230 --> 00:29:55.380 Mark Kushner: so because the energetic particles they don't actually collide. Very often their distribution function. It's more. You have to treat them more like particles. So this is our way of like looking at energetic particles. In in topology face they have different types of orbits, so the blue dots are mutual beam particles, and but there's different types of orbits. These are trapped orbits where particles reflect, and they make these sort of banana orbits. There's passing orbits where particles just keep going around and around. 116 00:29:55.380 --> 00:30:19.880 Mark Kushner: and then some of the orbits are. If there's, you know, they start in the plasma. But if there's just a small change in, say, their energy or their momentum type thing through energy exchange. Then they can become lost, and they can go on lost orbits. And so what happens is Alfie Nagin modes. They will grow because of gradients. This is a very common thing that happens in nature. Whenever you have gradients, it often drives instabilities. 117 00:30:19.880 --> 00:30:40.820 Mark Kushner: So for energetic particles, instabilities can be grown by gradients in in spatial distribution or energy distribution. And and then this is what where the the a single Alpha and Eigen mode might live in phase space. So wherever the alpha n eigen mode frequency overlaps with the frequency sort of up the fast Ion you can expect to have transport. 118 00:30:40.820 --> 00:30:50.860 Mark Kushner: This is for a single mode. And so you're like, well, how do I calculate how much transport from a single mode. That's kind of difficult. You have to treat all these individual orbits. It takes a lot of expensive calculations. 119 00:30:50.920 --> 00:31:19.059 Mark Kushner: but in reality, what we often see in experiments is, there's lots of. And they end up basically painting all of fast eye and face base for almost all of the fast science or being transported by these modes. And and so I just wanted to communicate that this is it's a phenomenon that we've seen in in other places, too. But what the practical implication is is when you're running experiments, say on D, and you start injecting more and more bean power. This is more and more fast ions. 120 00:31:19.060 --> 00:31:25.049 Mark Kushner: and and you measure the profiles. So you're increasing your fastign population as a measure of density. So 121 00:31:25.050 --> 00:31:44.569 Mark Kushner: going, going and then, now, I'm starting to in increase the power of my beams. But the profile is not going up. I should be injecting more fast science, but they're being transported by Alpha Nagin modes, and you reach what's called a critical gradient, and the mechanism is as simple as this. Like, if you're trying to like force in on a sand pile, you can only get to a certain critical gradient. 122 00:31:44.570 --> 00:32:07.140 Mark Kushner: and and there they happen in nature a lot. The idea is that as you have this gradient drives and instability instability transport particles, and then that causes the gradient to flatten and the modes will stop growing. So critical. Gradient transport is kind of a common. It happens in in Tokamax, not only with fast ions, but with thermal population as well. 123 00:32:07.520 --> 00:32:29.229 Mark Kushner: and just to say it has some interesting implications for how you do it. It simplifies how you model these systems. And and not only for energy. This is just showing like, Hmm, there's different fidelities and models, basically for any physics area. This is just from my world of energetic particle physics where there's simplified models. And then there's more and more complex models that treat all the details of face space. 124 00:32:29.330 --> 00:32:52.630 Mark Kushner: And so if if we're trying to design a reactors, it's very useful to have some of the more simple models, so that you can check things like our Alpha Niger's gonna be unstable. And how much impact will they have on the password population? This is really good for initial reactor design. And then, as you get towards a point where you're trying to vet an operating point, you can make make use of 125 00:32:52.700 --> 00:33:18.770 Mark Kushner: the more precise models? But in in general, I just like this is an example of using the critical gradient model. It's it's the way that you simplify the model is that you? You just have to calculate what what the growth rate is in the modes, and then you flatten the gradient until the mode stops growing. So all you're doing is cre is just calculating. Growth rates in this case, and that makes it a lot simpler model than some of the more complex ones. 126 00:33:18.770 --> 00:33:33.619 Mark Kushner: They have to go into like nonlinear saturation of ample feed, anyway. Okay, so what are these models predicting? Well, in like eater. They're pretty. They're predicting alpha particle populations that would look like the red line instead of the black line. So that's like a lot of transport. And 127 00:33:33.650 --> 00:33:51.369 Mark Kushner: the important thing is that pilot plant studies that we've been doing. We haven't actually included physics based energy particle transport when we're designing reactors. So this is really exciting new frontier when we're actually incorporating some of these simplified models in when we're analyzing the core plasma performance 128 00:33:51.510 --> 00:33:57.079 Mark Kushner: so beyond that one of the other big challenges is is actually 129 00:33:57.360 --> 00:34:21.309 Mark Kushner: handling the particles in in the plasma, so plasma particles will are not perfectly confined. They will leak out of the core, and then they will interact with plasma facing components and in Tokamax, if you can channel the particles down to what's called the diverter, you can pump them out with vacuum systems. And this helps to reduce contamination of the core plasma. And it really improves performance. 130 00:34:21.360 --> 00:34:40.479 Mark Kushner: And it also helps as you have alpha particles that slow down, they become ash, and you have to pump them out as well. So that's what the diverters for, in a token, Mac. But in a reactor it's something like it would be like a steady state rocket nozzle and you have to keep materials 131 00:34:40.489 --> 00:34:56.669 Mark Kushner: alive at at those heat fluxes, and you want to be able to operate for a long time scale if you want to have enough electricity to the grid and so this means that this is major materials challenges. And you have to have really good surface 132 00:34:56.699 --> 00:35:25.689 Mark Kushner: cooling techniques. And and it's one thing to solve these problems in isolation. But the new frontier that we really have to do is solve everything together in an integrated way. So the core, of course, is, for you have to have a high performance core making all the fusion and the neutrons. And you wanna be able. But you wanna be able to produce it without having a lot of control. And all these extra control systems? Because if you have a bunch of, say, microwave systems that are making holes in the blankets. 133 00:35:25.690 --> 00:35:52.129 Mark Kushner: Then you're taking away the area of the blanket to actually breed tritium. So there's also as as you're producing a high performance core. You have to make sure you don't melt the walls if it's too high performance, and you don't wanna melt the diverter. So all of this has to be treated in sort of an integrated way and and not in isolation. And so we're working on trying to find better operation points for for took. Max. This is sort of a plot of 134 00:35:52.130 --> 00:35:56.769 Mark Kushner: the world of Togamax scenarios. Fusion power is 135 00:35:56.900 --> 00:36:25.760 Mark Kushner: is on the left. Bootstrap current is. It's the actual plasma creates own current, which is sort of a magical thing. It. It's described here, but whenever you have gradients you have more particles going one way than the other. Then that drives sort of a self. A self driven current is a little more complicated than that. But anyway, this axis is talking about how much current the plasma can create on its own. And then this axis is talking about fusion power, which is it goes like 136 00:36:25.760 --> 00:36:38.809 Mark Kushner: the beta, and which is the the ratio of thermal and magnetic pressure and magnetic field and geometry properties, anyway. So devices like eater and spark, are planning to to operate over here where it's post plasma. 137 00:36:38.980 --> 00:36:49.470 Mark Kushner: and Ne sort of the frontier. Other devices are trying like maybe smaller aspects. Ratio Tocomax are are setting more of a steady state type 138 00:36:49.490 --> 00:37:09.839 Mark Kushner: where you you would actually not. The plasma would generate all of its own current. And and or you would also add external current drive, but you wouldn't rely on the plasma to generate a current from induction. So this makes it so you can actually have, like a steady state Tocomac and one of the advantages is that if you're over here on the post side. 139 00:37:09.840 --> 00:37:22.280 Mark Kushner: this is a database of like all the shots in, if you have high currents over here. You're operating next to a current limit and you get disruptions. But if you could operate over here in a steady state regime 140 00:37:22.280 --> 00:37:35.700 Mark Kushner: then you would have less likely to get disruptions. So just finding better operating points can solve problems. And also, as far as engineering problems going beyond the plasma. 141 00:37:35.840 --> 00:37:37.680 Mark Kushner: Steady state is somewhat 142 00:37:37.860 --> 00:37:48.440 Mark Kushner: Should you have upholst or steady state device? Thinking about the engineering post is not trivial. So depending on your blanket concept. 143 00:37:48.520 --> 00:37:56.830 Mark Kushner: There's there can be many, many interfaces. And if you're pulsing things, you're especially if there's thermal changes 144 00:37:56.840 --> 00:38:06.300 Mark Kushner: in in materials. It it destroys things very quickly. So there's cyclic stresses from expansion and contraction. There's material fatigue. 145 00:38:06.300 --> 00:38:29.260 Mark Kushner: And especially if we have that high heat flux going to the diverter, you're gonna have a plasma on plasma off. You're gonna be going through lots of heat flux and temperature transitions which can cause materials to crack. So these are some of the engineering things you have to think about when you're picking a scenario for tocmak. And there's also things beyond just collecting energy. It's when you're trying to convert it into electricity. 146 00:38:29.260 --> 00:38:55.559 Mark Kushner: Heat exchange systems like this is a very simplified drawing. And I'm not gonna go through all the details. But it's just to say that these systems are are sort of built for steady state, and there's a lot of complications that happen if there's thermal exchange is not sort of constant, anyway. So we still haven't gotten to the point where a post versus a steady state reactor has been analyzed in a integrated way. And this is still to do so. 147 00:38:56.200 --> 00:39:01.849 Mark Kushner: That's all I have to say about the controlling, sustaining, predicting a burning plasma, and that was the easy part. 148 00:39:02.750 --> 00:39:21.469 Mark Kushner: The the hard part is finding materials that can handle the extreme conditions. A. A. And so I'll talk a little bit about all that. I mean. I think some of you are involved in materials interactions at low temperature plasmas. And it's it's the same same thing. It's same thing. It's there. So there's so many. 149 00:39:21.470 --> 00:39:43.990 Mark Kushner: There's heat particle flux. There will be neutrons, and there's all different types of things that can happen to material surfaces in response to all of this. And and many of these things are convoluted when you have high temperature and high stress, or you have a chemical environment where you have corrosion. Cooling liquids are metals interacting with 150 00:39:44.010 --> 00:39:50.819 Mark Kushner: metal surfaces that can cause corrosion. And then when you add irradiation to it, things can grow and 151 00:39:50.970 --> 00:39:59.380 Mark Kushner: get larger, and that you can imagine for various precise engineering components the growth from from neutron 152 00:39:59.380 --> 00:40:24.369 Mark Kushner: creep and things is is not good. So this is a huge field that needs a lot of work, ideal fusion materials. They would be good for the plasma. They wouldn't melt, and they wouldn't degrade the plasma quickly or contaminate the plasma, but they also need to be sustainable, so that as they are activated by neutrons, they, the radiation activation is not long lived, and you want to be able to have materials that can last long enough. So you don't have. 153 00:40:24.370 --> 00:40:28.059 Mark Kushner: You have to keep shutting down your reactor and replacing them frequently. 154 00:40:28.380 --> 00:40:48.889 Mark Kushner: But we can. We can use resources, start developing these. There's many techniques advanced manufacturing to develop the materials. We can start to do some of the nuclear evaluation in fission type reactors, especially for materials that are more structural that are further out away from the plasma 155 00:40:48.890 --> 00:41:10.620 Mark Kushner: and and we have much machines coming online that are gonna be looking at plasma exposures where you could use a sample. And you could basically expose it to a plasma in 2 weeks, and that would be equivalent to the lifetime that that component would see in a reactor. So we're hoping to make progress using these types of systems 156 00:41:10.810 --> 00:41:12.040 Mark Kushner: and materials. 157 00:41:12.090 --> 00:41:28.270 Mark Kushner: you know, on the harnessing the fusion power part. This is even lower. Trl, so it's much more about doing simulations at this point, and these are examples of the required multi-disciplinary sort of assessments that are that are going on. So people take 158 00:41:28.270 --> 00:41:54.720 Mark Kushner: full CAD, or maybe sweeps or slices of the CAD, and then they do neutronics, assessments to find where the energy is deposited, deposited, or the materials are activated. Shutdown dose rates, and looking at thermal mechanics. A lot of this stuff is done routinely in fission, so you can look at displacement and the blanket temperature. How hot will the magnets get if neutrons are not properly shielded from the magnets. 159 00:41:54.820 --> 00:42:14.190 Mark Kushner: and people look at thermal hydraulics. Where? Where, how do you cool the blankets and with helium, for example. And so this gets into very high fidelity type simulations. And also people can look at. You can look at tritium breeding, and how tritium migrates through systems. So these are just examples of the types of assessments that are occurring. 160 00:42:14.190 --> 00:42:26.219 Mark Kushner: And so then, like, at this point, you're probably like, wow, this is a lot going to get fusion to work. And but you can start to look at these things and and say, Well, okay, in an integrated system. 161 00:42:26.270 --> 00:42:31.170 Mark Kushner: How important are the different R. And D 162 00:42:31.270 --> 00:42:55.080 Mark Kushner: pieces of the puzzle, and and which ones would make the most impact on the cost of of of building a fusion pilot plans or making it work. And but I mean it comes down to those 3 things that I was talking about. If you have a good confined plasma that has a big impact on the estimated capital cost of a plant, if you are, have good blankets that capture and breed tritium that has a big impact. 163 00:42:55.210 --> 00:43:16.590 Mark Kushner: And then having, you know, materials that can handle neutrons and heat flux, these are the big areas that we really need to invest in. And things like, actually, the different types of magnets are sort of, you can see how much of a difference it would make to use the high temperature superconductors versus the low lower temperature, superconductors that already exist. 164 00:43:16.620 --> 00:43:22.399 Mark Kushner: So this brings me to the last part. How do we put all this together? 165 00:43:22.960 --> 00:43:40.710 Mark Kushner: If you were to say, Well, where are we on the Trl level? Comparing the 3 different science drivers? People generally think that burning plasmas are to the point where, even though we haven't in necessarily made one in fusion, magnetic fusion, energy, we have pretty good idea of what will happen 166 00:43:40.710 --> 00:44:01.980 Mark Kushner: as far as handling reactor relevant conditions materials. We can borrow a little bit from vision in in that world. But it so it's plausible. But then I don't know the hap capturing energy with a blanket. We haven't. We haven't done any of this yet, so this is where we are in general, and so how? How do we go from here? 167 00:44:02.000 --> 00:44:11.629 Mark Kushner: one of the things I'm really excited about, especially as we need to make progress quickly is using really sophisticated simulation tools. 168 00:44:11.820 --> 00:44:24.319 Mark Kushner: So I am an experimentalist by training. We, I know we need to build things. You have to prove you can actually build something. And we have made remarkable progress, and things are getting built like eater and spark. 169 00:44:24.610 --> 00:44:53.100 Mark Kushner: But again, these are far from the regime that a fusion pilot will be in. And as much as we'd like to say that we wanna build devices quickly and iterate. It takes time. It takes money, and it's gonna take a lot of people so even now we're still waiting for some of them facilities to come out from as we made a community plan. And we said, these are priority facilities. Actually, none of them have started anything new. I mean, there's Mpex. But that one was already started before the community plan. 170 00:44:53.100 --> 00:44:59.850 Mark Kushner: So we have to do something, and simulations can fill a big role here. Simulations can help us save time. 171 00:44:59.850 --> 00:45:15.729 Mark Kushner: They can catch issues when you integrate systems together, so that when you actually do build a fusion pilot plan, it will be successful because you've caught a lot of issues ahead of time simulations, guide designs all the time. So they help you to de-risk 172 00:45:15.740 --> 00:45:27.500 Mark Kushner: different options for designs, because you're using physics based predictions. And if you can incorporate uncertainty, you can do things like design under uncertainty. And and they help you to 173 00:45:27.590 --> 00:45:36.809 Mark Kushner: figure out new ideas because you can experiment in a virtual test bed, using your creative thoughts to try to see how new new ideas would work. 174 00:45:36.900 --> 00:45:55.060 Mark Kushner: And in general simulations are gonna be needed in fusion anyway, because we need to prove that fusion is safe, and it's it's economical and scalable. And many of the evaluations for especially deuterium tritium devices will need to show that there's good shielding. There's trertium management and the materials. 175 00:45:55.140 --> 00:46:20.200 Mark Kushner: the Mir materials, activations and lifetimes will need to be known before before devices are built. So anyway. So I'm really excited because there's a new. We have a new side act project that's working on this. It's called Frida fusion reactor design and assessment. It's a big collaboration with Oakridge Laurence Livermore, Sandia, General Comics and Ucsd. And the mission is really to use many of the tools we already have. But to develop 176 00:46:20.380 --> 00:46:49.539 Mark Kushner: this capability to do integrated fusion, plasma and fusion engineering. And just to say a little bit more, I mean as fusion pilot plans have been designed in the past, or at least sort of initial design. Studies generally start with systems codes which are very generalized sort of 0 d empirical. Basically like spreadsheets. Find. Maybe this is the plasma design point and size of it. And then humans end up spending a long time to draw the geometry in the CAD, 177 00:46:49.540 --> 00:47:10.280 Mark Kushner: and then you check the feasibility with high fidelity simulations. And then, if you want to make a usually you'll find that. Well, this empirical scaling wasn't very good at at actually predicting what a plasma like actual profiles would be, and things. And the design point is not necessarily feasible. And you want to change something, it takes forever. So we're really trying to speed this process up by 178 00:47:10.350 --> 00:47:29.840 Mark Kushner: adopting iterative design and building up this medium fidelity level. So we can catch show stoppers before we get to really high fidelity assessments. And just to say, sort of the the structure of this is, we've already done a lot in the plasma community over the past decade. All of the coupling between 179 00:47:29.840 --> 00:47:43.140 Mark Kushner: the core pedestals, grape buff layer type plasma. There's been so much investment, and it's ready to go. There's been a lot of investment in fusion engineering side of things, especially in the past 3 years, to connect all of these engineering tools. 180 00:47:43.200 --> 00:47:59.879 Mark Kushner: and we also even have the ability to draw CAD with code rather than people. We can do all this stuff. So this project is really bringing all these things together, and and being able to very flex, do flexible design of either components or full systems. 181 00:47:59.950 --> 00:48:28.290 Mark Kushner: And so we hope to be looking at all the different types of integrations that need to happen to address various issues in the science drivers that you see like, you know, making sure you have enough shielding for the magnets, maybe in pictures. This is this is the way to think of it. We'll be able to do things like, create the plasma scenario, draw the first wall, the blanket. The magnets can already do this, and then assess 182 00:48:28.590 --> 00:48:36.950 Mark Kushner: the neutronics and see what gets hot, and maybe oh, I'll be at the point where. 183 00:48:37.040 --> 00:48:51.930 Mark Kushner: if I want to know how much impact energetic particles in transport has on the plasma and the rest of the system, I'll be able to test it in this integrated type setup and find oh, well, my magnets are getting too hot, and I need to change my scenario or something. 184 00:48:51.990 --> 00:49:00.110 Mark Kushner: So we we're really looking forward to this. It's just getting started. And I think this is going to be exciting for the path forward. So sort of to summarize. 185 00:49:00.170 --> 00:49:08.260 Mark Kushner: creating a sign on Earth. It's a grand challenge for for the 20 first century is this part of National Academy of Engineering. It's been listed 186 00:49:08.300 --> 00:49:23.030 Mark Kushner: and so you might just be wanting to know, when are we gonna get fusion? And I just wanted to end with this, because I do think it's important to realize that anytime you're building a new energy source. It takes a lot of investment 187 00:49:23.030 --> 00:49:46.430 Mark Kushner: time. And in this plot of, say, exponential R&D versus going into linear growth and then saturation, we're actually producing electricity. Fusion is about here. And in order just to get here, you need at least 20 billion dollars a year for 20 to 30 years to get here. This is how, if you look at any other energy source like fission wind 188 00:49:46.430 --> 00:50:10.210 Mark Kushner: solar. All of them have received billions worldwide investment per year, and fusion receives has been receiving like 2 billion a year. You can say, private industry has raised like 6 billion in the past 3 years. But to put in perspective, we need a lot more than than what we currently have. So hopefully, as we are starting to make headway on this. We will see more growth, not only in the private 189 00:50:10.210 --> 00:50:28.190 Mark Kushner: industry. But as governments around the world are investing, if we can unite our efforts. I hope it will, it will come together. So okay, you're probably feeling like this bird right now. I'm sorry for that. This is how I feel every day. Probably makes your has been. But I think fusion is a really good 190 00:50:28.190 --> 00:50:51.929 Mark Kushner: jobs. First job security and career option, because it's probably gonna be be of interest for many years. So I think maybe the takeaway points are that we have really good plasma and engineering modeling tools. We're bringing them together. We're gonna be utilizing them to make integrated progress of designing fusion. Pilot pants make progress faster. And and we're really committed to this, at least in my organization 191 00:50:51.930 --> 00:50:58.540 Mark Kushner: with trying to address the key issues like materials like, it's technology. So you can. You're welcome to check us out anytime. 192 00:50:58.540 --> 00:50:59.820 Mark Kushner: Thanks 193 00:51:09.170 --> 00:51:10.710 Mark Kushner: fence from the Apollo group. 194 00:51:12.610 --> 00:51:22.220 Mark Kushner: Oh, 79 slides. Sorry. 195 00:51:22.460 --> 00:51:35.609 Mark Kushner: Okay, that is one from online from David Smith. Who asked, is it possible to use software modeling to protect any of the impacts or off physical models needed in some areas? 196 00:51:37.470 --> 00:51:45.830 Mark Kushner: Right? So it, yeah, yeah, this, I mean, this varies on each individual field and validation level. 197 00:51:46.380 --> 00:51:49.090 Mark Kushner: let's see. So I you know. 198 00:51:49.190 --> 00:52:12.390 Mark Kushner: in in some of some of the areas, even like for fusion neutrons. We don't even have experiments to do these studies. So we actually rely on theoretical models to say, what's gonna happen in other areas? I mean, it's been really well tested on multiple devices from plasma physics, profiles, things like that. So it really depends on each individual area. 199 00:52:12.520 --> 00:52:32.610 Mark Kushner: the degree of of validation. But valid, I mean, that's the thing, though, validation is really important. And as we're putting these modeling tools together. We don't. It's not like we can validate it on the Fusion pilot plan because we don't have one yet. So you have to use different sort of experimental setups to just do individual tests on each different component. Yeah. 200 00:52:33.300 --> 00:52:38.630 Mark Kushner: alright, that's a question. Can you? Go to the 201 00:52:39.040 --> 00:52:43.180 Mark Kushner: it's like self correcting. 202 00:52:44.500 --> 00:52:48.680 Mark Kushner: Click slide 51 52. Yes. 203 00:52:48.730 --> 00:52:53.969 Mark Kushner: sorry. There's there was a lot of overlays. It wasn't actually 204 00:52:57.200 --> 00:52:59.199 Mark Kushner: yeah. Here. Yeah. 205 00:53:00.230 --> 00:53:21.979 Mark Kushner: Okay, awesome. So you would describe that. There are these like granular systems where you get a gradient that's too large, you know, like self correct, and then itself out. And that Bootstrap current relies on those gradients. So is there like a known like critical gradient where you're not gonna get any more bootstrap current to 206 00:53:22.010 --> 00:53:49.180 Mark Kushner: stabilize yourself. Yeah, right? So, well, okay, yeah. So in the pedestal, say, this is the edge of the device where you get a large gradient and pressure, and at some point in the Tokamak. When you have a very strong pedestal, you have a large gradient, and you run into either current or pressure limits, and you start getting elms. These are peeling ballooning modes, right? So you can't actually get a higher gradients in the pedestal because of elms. So that's a limit, I guess. And 207 00:53:49.180 --> 00:54:02.289 Mark Kushner: there, so people do things like try to change the edge profiles flatten them more so that you can push higher. See? Avoid elms. Kind of thing. That's an example. Yeah. 208 00:54:02.290 --> 00:54:18.950 Mark Kushner: Do you have a personal opinion on going for multiple, say, smaller, higher pressure, spherical talk, events versus one big multi gigawatt traditional high spec ratio talk for economic power. 209 00:54:19.660 --> 00:54:39.719 Mark Kushner: Yeah. So I mean, in general, people will try to say, the power industries are moving towards smaller module reactors like in fission, something that it doesn't take such a capital cost to build. So this is sort of driving the direction of the Us. Approach to having a compact high power, density, sustained reactor 210 00:54:40.680 --> 00:55:07.479 Mark Kushner: in. In reality, we I mean, as far as there's much to do and a aspect ratio optimization in the milestone program. There's a company doing a spherical tok, another one doing more conventional or maybe compact. But there's so like, there's a continuum in my mind of. And and we haven't actually really done aspect ratio optimization of what is the ideal size? Because, as you go smaller, it's really going to be limited by the inboard side. Like. 211 00:55:07.480 --> 00:55:19.359 Mark Kushner: if you're gonna have a central solenoid, you're gonna have to protect and shield the magnets so you can't go too small there. But then also, as you get higher energy density, it's pushing up the 212 00:55:19.360 --> 00:55:32.639 Mark Kushner: powered and C to the diverter and eventually run into materials limits. So there's also, if you have really strong magnetic fields, these Co tutorial pull field coils have much more stresses. And you have to actually build 213 00:55:32.710 --> 00:55:41.459 Mark Kushner: support structures around them. So you can't get too small either. And there's remote maintenance. How are you gonna actually change? Get into fix things if it's too small. So 214 00:55:41.470 --> 00:55:46.659 Mark Kushner: these types of optimizations are yet to be done, and export 215 00:55:47.610 --> 00:55:48.550 not your father 216 00:56:05.260 --> 00:56:07.479 Mark Kushner: sacrificial limiters 217 00:56:07.580 --> 00:56:37.490 Mark Kushner: as the first wall, so that a lot of I mean the actual blanket, the fusion blanket you. The first layer has to be very thin in order to let neutrons through at full energy, so they can breed more efficiently, so you can't have like a giant thick first wall, Eater has a giant thick first wall, and just because it's not, it's purpose is not to build free tritium so. But anyway, in order to protect a very thin first wall, you can actually install sacrificial limits, and those types of things would be something you would replace 218 00:56:37.550 --> 00:56:47.350 Mark Kushner: more more quickly. And yeah, so this is where it is like what you know, what components are gonna have to be replaced or frequently, and what will fail first. And 219 00:56:47.750 --> 00:56:50.830 Mark Kushner: this is something we need to study. 220 00:57:05.160 --> 00:57:21.059 Mark Kushner: Actually, the thing that would make the biggest. Yeah, this is why, people are. 221 00:57:21.120 --> 00:57:26.990 Mark Kushner: you know, really trying to explore different scenarios like, it's a high confinement. But again, it's 222 00:57:27.440 --> 00:57:53.340 Mark Kushner: it's yeah. It's an integrated issue with like, even if you had a very, very high high performance for plasma, you could end up just melting the walls, or whatever, so it has to be sort of an integrated approach to choosing. But yeah, I mean, and this is the same, for, like, we're accelerators are at right now, they're still trying to get good enough demonstration of confinement quality, and some of this will be assisted by ha! High power or high. 223 00:57:53.850 --> 00:57:57.089 Mark Kushner: yeah, higher magnetic field strength. But 224 00:57:58.360 --> 00:58:08.280 Mark Kushner: it's just a quick one. Can you go back to your final slide? The speaker box on the bottom right prevents you from getting the 225 00:58:08.870 --> 00:58:11.140 Mark Kushner: appreciate that. That's great. 226 00:58:11.620 --> 00:58:27.729 Mark Kushner: Yeah, you can steal signs. I won't get mad. 227 00:58:28.320 --> 00:58:32.279 Mark Kushner: I need to last 228 00:58:32.510 --> 00:58:52.149 Mark Kushner: schemes and drivers, and different physics that they have to study to make those work. Some of the issues are sort of similar between them. Their plans or efforts to sort of combine forces on some of the common issues, like 229 00:58:52.160 --> 00:59:00.750 Mark Kushner: radiation, hardness of materials or collecting energy from neutrons, cause at their heart 230 00:59:00.880 --> 00:59:25.809 Mark Kushner: same process and collecting them and their fluxes are probably pretty similar. Yeah, right? There are actually exactly this is happening right now. So there's, for example, a materials workshop that's involving various stakeholders from industry and national labs and universities which are discussing. Ha! What? How are we going to develop materials from 231 00:59:25.810 --> 00:59:32.729 Mark Kushner: where we are today? And we're some of the I mean, the whole point of sort of some of the community plan process was to try to bring out the common. 232 00:59:32.800 --> 00:59:57.769 Mark Kushner: you know. So I mean they they had, for example, about a year ago. Now they had another workshop on. Do we need a fusion? Prototype, neutron source? And again the answer was, Yes, the same answer that they came up with like in the early nineties. So there, in these contexts of things, multiple people, yes, will benefit. Multiple companies will benefit from following through, especially with the lower Trl step of materials and blankets so blanket 233 00:59:57.770 --> 01:00:04.570 Mark Kushner: component test facility that could multiple industries could test their concepts. All of that is being discussed 234 01:00:04.570 --> 01:00:07.289 Mark Kushner: and important. Yep, thanks 235 01:00:10.840 --> 01:00:17.680 Mark Kushner: alright. Is there a no more question. 236 01:00:22.180 --> 01:00:22.870 pop. 237 01:00:30.140 --> 01:00:31.709 Mark Kushner: Thank you very much. 238 01:00:31.950 --> 01:00:40.619 Mark Kushner: Starting the first poster session at 3 30, between now and 3 30. Please set up your posters. 239 01:00:40.720 --> 01:00:47.069 Mark Kushner: That will be in the atrium of the Ecs Building. I'll do the hallway. 240 01:00:47.080 --> 01:00:53.050 Mark Kushner: Turn right out the doors, and you'll see the atrium right in front of you. 241 01:00:53.060 --> 01:00:54.489 Mark Kushner: But thank you. 242 01:00:54.880 --> 01:00:58.539 Mark Kushner: Oh, yeah.