OF INTEREST: Dhiraj Bora on fusion

Dhiraj Bora, present Director of the Institute for Plasma Research, Gujarat and former ITER Deputy-Director General, explains what a fusion reaction is, what conditions it requires, and what hurdles scientists face in achieving it.

Read ​Prof. Dhiraj Bora’s interview here.


The monster that pulled people out of their homes

The passage of an exceptional convoy is a common sight for the inhabitants of the villages of Berre, Rognac, La Fare-les-Oliviers or Lambesc. The area, close to the harbour in Marseille, is heavily industrialized: steelworks, refineries, the aircraft industry … all depend on the delivery and expedition of large-size loads that travel the roads to the general indifference of the local population.

It takes something really exceptional to pull people out of their homes, old and young alike, and bring them to the roadside to ogle and gawk.

On Monday night, 16 September, the 352-wheel, 800-ton trailer mimicking an actual ITER convoy did just that. As it commenced its four-night journey between Berre and the ITER site in Saint Paul-lez-Durance, hundreds of people were lined up along the roads, some of them in nightshirts and pyjamas, to watch the long procession of men and vehicles slowly advance along the first stage of the 104-kilometre ITER Itinerary.

The event, which aims to monitor the behaviour of roads and bridges under the extreme ITER loads, was the culmination of five years of hard work and complex calculations by the French public roads administration and the technical services of the Bouches-du-Rhône département. As ITER Deputy Director-General Rem Haange explained prior to the departure of the convoy, „The ITER Itinerary is essential to the project. It is the indispensable link between component fabrication in the factories of the ITER Members and the assembly of the machine by the ITER Organization.”

It was around 10:00 p.m. when the convoy, organized by logistics service provider DAHER, left its parking area in Berre. Night had fallen one hour earlier and the headlights of the trailer, accompanying vehicles and gendarmerie motorcycles contributed to the eerie atmosphere—the monster had awakened and was ready to take to the road.

Its first stop, two hours and five kilometres later, was at the railroad bridge in Rognac, the first of the 35 bridges that dot the Itinerary. The bridge had been equipped with a whole array of sensors to measure the deflexion of the structure under the strain of the convoy. Calculations had anticipated some 32 mm of deflexion, measurements yielded 30 mm.

The test convoy will continue another three nights to the ITER site. As it progresses along the Itinerary, the measurement operations will be repeated at every bridge. Manoeuvring space and operational margins will also be checked at every turn and roundabout. Processing the accumulated data will take about one month and a half, but early on Tuesday morning, Pierre-Marie Delplanque, the man in charge of overseeing operations for Agence Iter France, was satisfied … and relieved.

„We had a couple of very small issues,” he said, „and in two or three places we can still make small improvements. However we did not identify any major obstacle and I do not anticipate any issue when the actual convoys are organized.”

The convoy arrived in a secure zone in the village of Lambesc at 5:45 a.m. Tuesday, 16 September. Operations resume on Tuesday night at 9:30 p.m., when the convoy will take to the road again and—following the same pattern of measurements—will proceed another 15 to 20 kilometres.

The test convoy is expected to arrive at ITER in the wee hours of the morning on Friday 20 September.

View more photos here.
View local (LCM-Marseille) and regional (France 3) public TV coverage in French.

Three cities, two Procurement Arrangements

During the week of 26 August, ITER Director-General Motojima travelled to Russia, visiting three cities and signing two Procurement Arrangements in four days.

Accompanied by Deputy Director-General Alexander Alekseev, head of the Tokamak Directorate, the ITER Director-General began his trip at the Institute of Nuclear Physics in Novosibirsk, where he signed the Procurement Arrangement for Equatorial Port 11 Engineering, for the engineering of diagnostic systems into vacuum vessel Port 11. The Budker Institute will be responsible for the scope of work.

The Budker Institute already plays a key part in the development of high-tech electron equipment, engineering of diagnostic systems into the vacuum vessel ports, and research into the investigation of high-temperature plasma impact on reactor’s first wall materials as well as developing, manufacturing, and testing equipment for the ITER machine.

According to the Head of the Russian ITER Domestic Agency, Anatoly Krasilnikov, equipment development for ITER’s plasma diagnostics engineering will take five to seven years and will require constant interaction with the ITER Project’s other partners. In all, the Budker Institute will develop five engineering systems for ITER’s vacuum vessel ports.

The delegation from ITER also visited the Institute of Applied Physics and the enterprise GYCOM in Nizhniy Novgorod, where gyrotron component manufacturing and assembly are conducted as well as the development of infrastructure equipment such as cryomagnetic systems, measurement and technological devices, and part of the energy sources required for the gyrotrons. Procurement of the ITER gyrotrons is a matter of special pride to the Institute of Applied Physics, because it was here that this device was invented. More than half of existing experimental fusion facilities in the world currently use gyrotrons from Nizhniy Novgorod.

The final destination stop was in Moscow. At Project Center ITER (the Russian Domestic Agency for ITER), Director-General Motojima signed the Procurement Arrangement for the Thomson Scattering diagnostic system, one of 21 systems that Russia will deliver to ITER before 2024.

A traditional Indian blessing for the Cryostat Workshop

In the Indian pantheon, Ganesha is the one who can remove the hurdles from the path of our human endeavours. In India, anything of importance—a wedding, journey or construction project—begins with an invocation to the elephant-headed deity.

Since a small portion of the ITER platform has been made available to the Indian Domestic Agency for the construction of the Cryostat Workshop, it was natural to place this football-field-sized piece of India under the protection of the „Remover of Obstacles.”

Throwing a bridge between the high-technology world of ITER and the Indian tradition of times immemorial, Bharat Doshi, Cryostat Section leader, first explained to his guests during a ceremony held on 6 June how the giant ITER cryostat will be assembled from 54 segments manufactured in India.

He then proceeded to „break the coconut” and share the coconut meat among the guests—a ritual that is also meant to appease Mother Earth, whose tranquillity will soon be disturbed by the construction works.

Once every guest had broken a coconut, a large excavator symbolically scratched the earth where the 26-metre-high, 110-metre-long Cryostat Workshop will soon be erected.

The same Indian company (Larsen & Toubro Ltd) that will manufacture the cryostat will also build the Workshop and manage the assembly and welding activities all the way through to the final integration of the cryostat into the machine.

„We have already launched the procurement process for the raw material,” explained Philippe Tollini, Larsen & Toubro’s director for Europe and Russia. „We are presently in the manufacturing design stage, which will be completed by September. We should begin to receive the first cryostat segments from India at the end of 2014, beginning of 2015.”

„The cryostat is an essential part of the ITER installation,” explained ITER Deputy Director-General Rem Haange. „It has to be absolutely leak-tight and its assembly requires kilometres of welding. It is a tough job not only to manufacture but also to assemble.”

Last fall, Larsen & Toubro awarded the construction of the 5,500 square-metre Cryostat Workshop to the French company Spie-Batignolles, which was part of the consortium that built the adjacent Poloidal Field Coils Winding Facility.

Construction should begin in earnest in the coming weeks and take a year and half.

Back in India, but keeping a foot in ITER

After five years as Deputy Director-General (DDG) and Director of the CODAC, Heating & Diagnostics Directorate at ITER, Dhiraj Bora returned to the Institute for Plasma Research in Gandhinagar, India in December 2012. In February, he was appointed Director General of the Institute. Newsline recently asked him to say a few words about his return to India, and his vision of the ITER project.
How does it feel being back in India after five years in France? Has there been a period of re-adaption?
I feel good to be back at the Institute for Plasma Research (IPR) in India after six years at the ITER Organization. Working style here is not exactly the same however; therefore, I needed a bit of time to readapt. I am also trying to implement some of the good practices from ITER.

Is there anything you miss about France?

Oh yes, my family and I miss a lot of things. As ITER is in its Construction Phase, life at work was different and hectic and I enjoyed that. Aix-en-Provence is such a nice place to live and interact with people that we will always miss that life.

Looking back upon your time at ITER, what were the most important moments for you—those you will remember, good or bad …

Learning to manage an international group of experts in the ITER Directorate for CODAC, Heating & Diagnostics was a very important experience for me. The good and the bad all came together for me at my farewell party last December: I was leaving colleagues with whom I shared all my time for six years, but I was happy to receive so many words and gestures of good will and appreciation for what I had accomplished in the CHD Directorate. 

Does now being on the „outside” change your perception of ITER? Do you feel that the outside world has a clear idea of the ITER project—its scope, stakes and challenges?

No, my perception of the project hasn’t changed although I am now looking in from the outside. ITER is a unique project and the outside world still needs to understand the differences and complexities of executing such an international scientific project, as compared to any other large project. More people like myself returning from the ITER Organization and continuing still to support fusion and the project should be able to recount these differences to the public to further strengthen their support for the project.

You have recently been appointed Director General of the Indian Institute of Plasma Research, a familiar place to you. How do you see your position there and what are your main priorities as DG?

I have grown with the Institute for the last thirty years. It is the premier institute of India for fusion research and my priorities will be to help the national fusion program grow faster and increase our contribution to the international program.

You will be back at ITER as a Council member. What do you expect from this new ITER-related mission?

As a Council member from India, my priority will be to support activities at the ITER Organization to keep the construction completion date within the parameters  of the 2010 Baseline. I hope to help the ITER Organization in completing design work in all possible ways.

First hardware afloat from China

On Thursday 25 April, the morning silence at the Institute of Plasma Physics (ASIPP) in Hefei, China, was broken by the noise of a high powered trailer. Inside the superconductor shop of ASIPP, workers were busy preparing to load the 737 metres of dummy conductor for ITER’s Poloidal Field Coil number five (PF5)—this represents the first delivery from China to the ITER construction site in France.
According to the Procurement Arrangement signed between the Chinese Domestic Agency and the ITER Organization, China will fabricate 64 conductors for ITER’s poloidal field coils, including four dummy conductors for cabling and coil manufacturing process qualification. ASIPP is responsible for all the poloidal field conductor fabrication in China. The fabrication of the PF5 dummy was completed in by ASIPP in 2011.
„This is the very first batch of ITER items to be shipped from China to the ITER site in Cadarache," said Luo Delong, Deputy Director-General of ITER China. Before, conductors for the toroidal field coils had been shipped to Japan and Europe. "This milestone is a further step for the ITER project. According to our schedule, we will now start massive production of conductors this year. Our goal is that all procurement items from China be supplied consistent with the ITER schedule and with ITER quality requirements.”

According to the shipment schedule the PF5 dummy conductors, which left Shanghai on 30 April, will arrive at the ITER site on 5 June.

Hot, hotter, hottest

Temperature, from a physicist’s perspective, is not only a measure of hot or cold.

It is also a measure of the energy carried by atoms and molecules: temperature tells us how rapidly these atoms or molecules move within a solid, a liquid or a gas.

Temperature is different from heat. To feel heat on your fingers, you need density: the higher the density, the more heat is transferred to your skin—this explains why a neon tube containing a very hot (~10,000°C) but very tenuous plasma can be touched without harm.

In temperature, there is a theoretical absolute cold („absolute zero”) but no absolute hot: a particle can always move more rapidly but it cannot be more immobile than … immobile.

When we talk about a 150- to 300-million-degree plasma in ITER, we’re describing an environment where particles (the deuterium and tritium ions and the freed electrons) move around at tremendous speed: so fast and with such a high energy that when they collide head on the miracle of fusion happens. The electromagnetic barrier that stands between nuclei is overcome and the nuclei can fuse.

How will the ITER plasma be brought to such extreme temperatures—ten times higher, or more, than the core of the Sun?

Plasma heating in ITER will begin with an electrical breakdown, quite similar to what happens when we turn on the switch of a neon light. In the very tenuous gas mixture that fills the vacuum vessel (one million times denser than the air we breathe) the electrical discharge strips the electrons from the atoms and the gas becomes a plasma—a particle soup of electrically charged electrons and ions.

„The electrons from the current collide with and communicate their energy to the ions from which they have been stripped,” explains Paul Thomas, ITER Deputy Director-General for CODAC, Heating & Diagnostics. „Current intensity grows steadily and, as plasma resistance increases due to the collisions between electrons and ions, temperature also rises—this is Ohmic heating, like in a bread toaster or an electrical radiator.”

However, contrary to what happens in metals, plasmas have an unusual property in terms of resistivity: the hotter they get, the less resistive they become. This means that Ohmic heating can heat a plasma only up to a point.

„For a long time,” Paul recalls, „some fusion physicists dreamed they would achieve fusion with Ohmic heating alone by increasing the magnetic field. Even today, the project called Ignitor is based on this assumption. The problem is that the more intense the magnetic field, the stronger the mechanical strain on the machine’s structure…”

Ohmic was the only heating source on the Soviet T-3, which achieved plasma temperatures in the range of 10 million degrees in the late 1960s—an achievement that left the nascent world fusion community agog and launched the tokamak race worldwide.

Achieving fusion, however, requires temperatures approximately ten times higher than what Ohmic heating alone can provide. In the 1970s, the fusion community began experimenting with additional heating techniques based on radio frequency (RF) waves, or the injection of energetic atoms into the plasma.

Yes, radio waves can heat. Whether at 40-55 MHz, like shortwave radio (ion cyclotron; a few GHz like microwave ovens (lower hybrid) or many tens to hundreds of GHz like very advanced radar (electron cyclotron), sending electromagnetic into the plasma can deliver enough energy to push it into the fusion regime. ITER will be equipped with an electron cyclotron and an ion cyclotron heating system, both delivering 20 MW of power.

But the workhorse of additional heating in tokamaks has been neutral beam heating—the injection of high-energy neutralized particles deep into the plasma.

Neutral beam heating is a bit like heating the milk in a pot by using a jet of hot steam from the espresso machine, what French garçons de café systematically do when you order cappuccino. As hot molecules from the steam jet collide with those of the cold milk, energy is transferred and hot milk is ready to be poured in the coffee cup.

„Exploitation of the neutral beam technologies we will use was pioneered in Japan,” says Paul. We have a very strong collaboration with our friends in Naka. Neutral beam technology is also used on JET (ITER’s neutral beam system will deliver seven times the energy of JET’s).

The challenging technology of ITER’s neutral beam system will be tested in a dedicated installation that was inaugurated a year ago almost to the day: the PRIMA Neutral Beam Test Facility in Padua, Italy. In parallel, IPP Garching is developing ELISE, an ion source half the size of ITER’s; success on this test bed will greatly reduce the risk associated with the final development of the full-size ITER ion source at the SPIDER test facility.

ITER’s three heating systems—electron cyclotron, ion cyclotron and neutral beam—feature different levels of technical complexity, maintainability and ease or convenience of use. The balance between these features is such that all three should be tested on ITER and developed to the point where a decision can be taken on which should heat a reactor, according to Paul.

„The reason we’ll have all three systems in ITER is to have them compete in the nuclear environment — this is precisely what the 'technological viability’ demonstration is about.”

The "Unique ITER Team"

A "Unique Team" for a unique project. From left to right: Director of the Department for ITER Project Rem Haange; Head of Korean Domestic Agency Kijung Jung; Head of the F4E ITER Departement and ancting DA Head Jean-Marc Filhol; ITER Organization Director-General Osamu Motojima; Director of US ITER Project Office Ned Sauthoff; Unit Manager, Division of ITER Projet at JAEA Eisuke Tada; Deputy Director-General of ITER China Luo Delong; Head of Russian Domestic Agency Anatoly Krasnilikov and Ujjwal Baruah, Project Manager ITER India representing Head of ITER India Shishir P. Deshpande.

Looking into the heart of the matter

The Helmholtz Association (34,000 employees, 18 research centres) is Germany’s largest scientific organization with strategic programs in six core fields, among them the development of fusion energy. The Helmholtz Association’s nuclear fusion program is currently pursuing two priority goals: to carry out Germany’s contributions to building and operating ITER, and to finalize and operate the Wendelstein 7-X Stellarator in Greifswald.

This week, the president of the Helmholtz Association, Juergen Mlynek, assembled the heads of the German fusion research institutes and paid a visit to ITER to get first-hand information about the project’s status. The group was welcomed by ITER Deputy Director-General Rem Haange who summarized the most recent progress before the bus took the group to the very heart of the matter, the Tokamak Pit.