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Mobile Fusion

It has been a while since I had time to put anything up on my blog. The blog was started a few years ago for me to explore the online experience. It was interesting to put my views online but I knew there would be only a few readers.

I put a little effort into promoting the site and I was delighted when I got a few hundred readers. However, there has been a much greater than expected interest in the site. I would like more comments but I get lots of readers.

What caught my interest in the last few weeks was the announcement from Lockheed Martin about their Compact Fusion experiment. I suppose we are getting a lot of business activity around mobile devices. The thought of a mobile fusion device seems really in the realm of science fiction. I remember back to the future had a car with a fusion engine. It was a Delorean car built here in Ireland, the fusion engine was of course invented by the film makers not the Irish researchers. We have little people and fairies here in Ireland but we have not cracked fusion yet.

The Lockheed Martin team claim that a working reactor could be built to fit on a truck. I like the idea that plasma could be used to solve the worlds energy crisis. However, I am skeptical of some of the more radical claims about breakthroughs in this area. I worked in fusion for a number of years and was a member of the Scientific Committee of JET, the most successful fusion device ever built. It actually achieved a fusion power of 4MW.

Lockheed say that they have a 1/2 scale device currently and they expect five yearly cycles to a working experimental reactor and a further five years to a fully developed fusion product. Their aim is to build a 100MW device that would be mobile and could be deployed easily.

My first reaction is that a small device with a quick development cycle could allow much more rapid development than is achieved in the government funded programmes where the cycle times are many years. I have learnt this working in industry as compared to academia. Where I am, in industry, we can turn around rapid development programmes in months that would take years in a university or government lab.

But will it work? Hard to say yet. There is some indication that they have developed a flexible magnetic confinement that adjusts to the plasma to give a high beta confinement. I will wait to see the paper before I comment anymore.

Even if it does work, it will be 10 years before the power flows and the team have focused on the plasma problems, but the materials problems associated with a burning reactor are immense. I firmly believe that if a €50B reactor such as ITER is difficult to design then a smaller reactor might be nice but will be harder. Remember fusion is easier to achieve the larger the reactor. That is why the sun works so well. It is huge.

I will await the first paper to see if they really have a game changer on their hands.

Pulsed Plasma Diagnostics Workshop, Early Registration Deadline Extended

I am delighted to be involved with this small, but exciting meeting being held here in Dublin on the 6th and 7th of September.  I published a number of papers in the 1990’s on pulsed plasmas, including a letter in Phys Rev Letters on efficient negative ions sources using modulated RF plasmas.  The idea of using pulsed plasmas to select the electron energy distribution function (EEDF) is now used in Semiconductor plasma etching.   Control of the EEDF is important in regulating negative ion flux, ion energy control and charging effects.  The best way to control anything is to make the right measurements. Plasma diagnostics in pulsed plasma are challenging and we are bringing together an elite group of experts in the area of pulsed plasma diagnostics to share their experience and improve the quality of plasma measurement.  The organizer is David Gahan and he has told me that  due to a number of requests the early registration deadline for the PPDW has been extended until the 29th June. Please register now to reserve your place at the reduced rate as places are limited.

http://www.impedans.com/announcements.html

Please find the 2nd announcement for the Pulsed Plasma Diagnostic Workshop (PPDW) attached. Pulsed plasma discharges are used for a variety of applications in modern industry. Magnetron sputtering and HiPIMS discharges, used for depositing layers, generally use pulsed direct current (pDC) excitation of the target and/or substrate to generate the plasma and control the layer properties. Operating frequencies range from 100’s Hz to 100’s kHz, typically.

Recently, there has been a move towards pulsed radio-frequency (pRF) discharge operation by the etching community where the rf driving frequency is pulsed in the 10’s kHz range. In these devices (inductively coupled (ICP) reactors, for example) the source and/or bias frequency are pulsed independently or synchronously to provide better control over the ion energy and etch properties. There are many other examples and uses of pulsed plasmas in the wider community also.

The purpose of this workshop is to gather a team of leading experts from the various pulsed plasma fields to share their knowledge and expertise in the art of pulsed plasma diagnostics. This will provide a unique opportunity for plasma physicists from different fields to interact and learn about diagnostic techniques that may now be applicable to their own research. A stimulating workshop, along with some exciting social activities, will make this an event to remember. Please visit the link below for more information.

Impedans Langmuir Probes

 

Plasma Fusion Device Gets Go Ahead from French Government

The International Thermonuclear Experimental Reactor (ITER) has finally been given the go ahead by French authorities.

The ITER organisation received a letter from the French Safety Authority, Agence de sûreté nucléaire (ASN), on 20 June 2012 which granted a license to build an experimental tokamak nuclear fusion reactor in the south of France.

Construction of ITER Authorised by French Government.

13th International Conference on Plasma Surface Engineering, Garmisch-Partenkirchen, Germany

The 13th International Conference on Plasma Surface Engineering will take place from 10 to 14 September 2012 in Garmisch-Partenkirchen, Germany. Plasma is an important tool for manufacturing high quality thin coatings. It is also an important component in the process of producing innovative new products and surfaces. For example, wet chemical and dry plasma treatments are used to synthesise functional materials, modify surface properties and produce engineered surfaces. The event will be an opportunity to learn more about the latest in research, development and industrial applications. Topics will range from fundamentals, to empirical studies, applications and industrial production.

I will not be going to Garmisch-Partenkirchen this year.  My first time to miss this excellent conference in the last 10 years. The conference is held every two years and draws a strong interest from german industry as well a good international audience. If you are a plasma scientist or engineer with an interest in the applications of plasma then this is a conference not to miss. Let me know your thoughts on the PSE conference.

For further information, please visit: http://www.pse-conferences.net/pse2012.html

For further information on plasma measurement tools click here

Fusion Plasma: a pipe dream?

A recent article by William Reville in the Irish Times throws cold water on the concept of fusion energy being a reality before 2100.  Fusion energy is similar to Fission (on which nuclear reactors depend) in that both are based on Einsteins famous equation E=MC^2.  Pronounced as E equals M C squared. E is the energy released and M is the mass destroyed and C is the speed of light. How is the mass destroyed? Well, nuclear particles will bind to each other using the strong nuclear force and will be repelled because of electrostatic forces. Therefore, an atom is a complex interplay of forces holding the atom together and other forces pushing it apart.  There is an optimum size for an atom, not too big and not too small.   So, taking two small atoms and adding them together to make a larger one makes a more stable atom and mass is destroyed to make energy. This is called Fusion Energy.  Taking a heavy atom that is above the optimum, somewhere near iron, and splitting it into smaller atoms also results in less mass and energy being released.

Thermonuclear fusion in a reactor requires a gas to be very hot, this can be achieved by using a fission reaction to provide the high temperatures such as seen in the Hydrogen bomb.  The atom bomb is a fission reaction which is easier to produce and this heats hydrogen to very high temperatures and causes the atoms of hydrogen to fuse to create helium. This is the basis of the H-bomb and it is a more powerful source of energy than fission.  Trying to contain a thermonuclear reaction inside a vessel in a continuous reaction is the holy grail for fusion research and would create a relatively cheap and safe nuclear energy technology. It is just possible to make this work using a magnetic bottle to confine the gas. The magnetic bottle works because at very high temperatures all the electrons are knocked off the atoms to form a dense plasma. The atoms without electrons in a plasma are called ions and they are directed by the magnetic and so can avoid hitting the walls and melting the chamber.

The main alterative to magnetic confinement is inertial confinement, here the gas is heated so quickly that the gas does not have time to get to the wall and melt it. This is a non-equilibrium reaction so it can be called non-Thermonuclear fusion.  Lasers can be used to heat and confine the materials and high energy beams can also be used.

Both Thermonuclear and Inertial Confinement have been shown to work and JET, the joint European thermonuclear reactor has produced many megawatts of fusion energy for several seconds. However, the next experiment, Iter is under construction and will take several decades to complete.  There is a joke in fusion research that a reactor is 20 years away no matter when you start the clock.

Fusion energy still a pipe dream by William Reville.

Why Lawrenceville Plasma Physics Results are Not Even Wrong; a Detailed Analysis.

I recently responded to a claim from Lawrenceville Plasma Physics that they were close to a commercial fusion reactor.  I was annoyed that such claims were being made and even more concerned that such claims were not receiving a strong criticism from the scientific community.  I read the paper published in the journal – Physics of Plasma by Lerner and his colleagues.  The journal is a reputable peered reviewed publication. It was clear to me that the paper was not significant. Dense plasma focus devices are well understood and have been modelled in detail. The results quoted by Lerner did not show that the focus device which he has developed was significantly better than other devices and there was no evidence that a commercial fusion device was any closer.

Read the full blog post — Lawrenceville plasma physics results are not even wrong detailed analysis 

Basic Plasma Parameters; Course in Plasma Physics

The third in a series of a basic course in plasma physics, Basic Plasma Parameters  explains the importance of the concepts of temperature, thermal speed and quasi-neutrality in plasma physics.  The page is accompanied by a short video.