Nuclear reactor lab session – remotely
In various ways, the pandemic has naturally forced us to come up with new solutions. For the nuclear engineering students, the pandemic means that their nuclear reactor laboratory session has to be conducted remotely between Ångström Laboratory and Ljubljana. But that has some advantages as it turns out.
Normally, students in the Bachelor Programme in Nuclear Engineering would travel to the Jožef Stefan Institute in Ljubljana to conduct a laboratory session at the Institute’s research and training reactor. But because of the pandemic, that isn’t possible. Instead, the students are doing their reactor lab session from a classroom in Ångström Laboratory.
Better than anticipated
reactor lab session from a classroom in Ångström
Laboratory. Photo: Mikael Wallerstedt
The students have access to a remotely controlled camera in the reactor’s control room that they control themselves and can direct at what they need to see at any given moment. They also have the feeds from a number of fixed cameras, including one above the reactor core, and an electronic whiteboard that both the reactor staff and the teachers/students in Uppsala can write on and read. Data links allow the students to remotely control the instrumentation for data collection and of course they also have Zoom meetings with camera on in order to see what is happening and discuss it with the reactor staff.
“When we first heard that we would not be allowed to travel to Ljubljana as we usually do for this laboratory session, I thought it would just be a Zoom meeting instead. But this has turned out really well,” says William Lindberg, a student.
“Yes, it’s definitely a good lab session, we are doing it for real. Yesterday, for example, we had to start and stop the reactor. And it’s much easier to control the reactor than I thought,” says Lars Vikström.
But isn’t it scary to control a nuclear reactor remotely?
“No, because there are professionals there in the control room. They tell us if we are about to do something stupid and they are monitoring everything on site,” says Lars Vikström.
And, like all nuclear reactors, of course, this reactor also has a number of functionally independent safety systems that monitor the reactor and shut it down if necessary.
Testing the reactor’s sensitivity
Right when we are visiting the lab session, the students are testing the reactor’s sensitivity to various parameters, including steam. When heat is released in a reactor, steam forms when the water around the fuel rods starts to boil. The higher the output of the reactor, the more steam is formed. The steam in turn moderates the neutron flux that keeps the nuclear chain reaction going. The more steam that forms, the more the output in the reactor is moderated, so thus becomes self-stabilising.
The research reactor is designed so it will shut down even at low water temperatures, so that you can instead blow air into the reactor core and thus simulate the impact of steam on the nuclear reaction.
“On the screen here you can see all the positions where we can pump in air and here you can see the flux. The larger round circles in black are the control rods,” says Lars Vikström as he points to what’s happening on one of the screens.
Advantages of a remote session
William Lindberg wonders if there might actually be some advantages in doing the laboratory session remotely.
“We have heard that in previous years when the students have been there on site, they have scarcely had time to think because it was such a tight schedule. We now have a session before and after lunch every day, and time to reflect in between,” says William Lindberg.
Michael Österlund, Senior Lecturer in Applied Nuclear Physics and programme coordinator, agrees.
“By saving travel costs for transport and accommodation in Ljubljana, we have been able to extend the laboratory work to a total of five days. The students have more time for data analysis, reflection and discussion in conjunction with and after the various lab exercises, which provides better conditions for understanding and insight. In some respects, the overview that students get during the laboratory exercises is also better than from the reactor control room because we use a number of large screens to simultaneously display control panels, equipment and the reactor core, which in reality are physically separated from each other.”
But of course there are also drawbacks with a remote lab session.
“The main drawback is that the students don’t get the experience of spending time and working in the reactor environment and that they cannot perform some of the practical tasks hands-on, tasks that the operators at the reactor now have to carry out when asked to by the students,” says Michael Österlund.
No training reactors in Sweden
Research and training reactors only exist in a handful of places around the world. Previously, there was one in Studsvik in Sweden, but it has been closed down.
“We have had good research collaboration with the Jožef Stefan Institute in the past, so it was natural to collaborate with them on the education side as well,” says Michael Österlund. “This is the first time we have conducted a remote lab session at a nuclear reactor and, as far as I know, it is the first time ever that it has been done in this way.”
Can you compare the workload for the teacher between these two variants?
“Since this is the first time, it has taken a lot of extra work to achieve a good learning experience and to acquire, deploy and also test the technical systems that are needed, here in Uppsala and in Ljubljana,” says Michael Österlund. “In addition to a number of Zoom links, we also use data links for remote control of the various technical devices/data collection systems in Ljubljana, remote control of motorised cameras and for an interactive whiteboard.
“For future laboratory sessions, now that the teaching and technology are set, the extra work will be less, and it might even mean a bit less work because we don’t have to travel long distances with the students and teachers.”