DMV - Department Of Motor Vehicles.Joseph Chikva wrote:What is "DMV"?ladajo wrote:I have to wonder what DMV looks like in the former Soviet Union...
Where you get tested and get papers saying you are qualified to operate a motor vehicle.
DMV - Department Of Motor Vehicles.Joseph Chikva wrote:What is "DMV"?ladajo wrote:I have to wonder what DMV looks like in the former Soviet Union...
RT, the news agency formerly known as Russia Today:MSimon wrote:I have been out of the loop for a while what is the RT video?Mike_P wrote:I have been reviewing the RT video piece
Thanks!Ivy Matt wrote:RT, the news agency formerly known as Russia Today:MSimon wrote:I have been out of the loop for a while what is the RT video?Mike_P wrote:I have been reviewing the RT video piece
http://www.youtube.com/watch?v=49p0cZEisTA
http://rt.com/usa/news/plasma-fusion-en ... clear-080/
Indeed, this seems to be the process that leads to "annealing". The tangential energy distribution of the ions at the well edge is broader (flatter) than MB and the ions bunch up toward a tighter distribution, thus they are "colder" (dethermalized, re-thermalized?) when they next fall into the well.ladajo wrote:Thanks, I'll think about this.93143 wrote:Not strictly accurate. It's possible to specify a distribution function that most people would agree is "flatter" than a Maxwell-Boltzmann distribution; in such a case, the thermalization process would steepen the curve.ladajo wrote:"thermalising" is flattening the distribution curve
Maybe. I'd be careful about this - remember that travelling up a potential well translates velocity-space scatter into spatio-temporal scatter (slower ions can't travel as far up it, faster ones reach the top earlier and with significant energy), which may then be compensated for by collisions and/or wave damping, etc....KitemanSA wrote:Indeed, this seems to be the process that leads to "annealing". The tangential energy distribution of the ions at the well edge is broader (flatter) than MB and the ions bunch up toward a tighter distribution, thus they are "colder" (dethermalized, re-thermalized?) when they next fall into the well.ladajo wrote:Thanks, I'll think about this.93143 wrote: Not strictly accurate. It's possible to specify a distribution function that most people would agree is "flatter" than a Maxwell-Boltzmann distribution; in such a case, the thermalization process would steepen the curve.
But also remember that the collisional x-section is inversely related to CoM velocity. As two ions with different velocities travel "up the well", their relative velocity (CoM velocity) is quite small so the x-section is large. If they aren't DIRECTLY in line, they will tend to normalize the radial velocity while spreading the tangential. Thus, they should reach the top with a more uniform RADIAL velocity. They then slow down (the well you know) and then the CoM velocity is almost all tangential. This will tend to "thermalize" into a tighter distribution, no?93143 wrote: Maybe. I'd be careful about this - remember that travelling up a potential well translates velocity-space scatter into spatio-temporal scatter (slower ions can't travel as far up it, faster ones reach the top earlier and with significant energy), which may then be compensated for by collisions and/or wave damping, etc....
If you when saying "a tighter distribution" mean "lower temperature" and ,so, "lower internal energy" - then, no.KitemanSA wrote:This will tend to "thermalize" into a tighter distribution, no?
So, for lowering of temperature you need not a "closed system" but the system dissipating energy into environment in some form. Any internal interaction e.g. collisions will not help for claimed by you purpose (lowering of temperature).First Law of Thermodynamics:
The total amount of energy and matter in the system remains constant, merely changing from one form to another.
Yup, in essense. Thermalization in the low k.e. region tightens the broadened distribution that was initiated by thermalization in the HIGH k.e. region; thermalization, counter-thermalization..ladajo wrote:As I understand, and posted even the reference, annealling is a combination of effects that occur as particles approach, enter, and then depart from the "turn-around" region. This combined effect, in turn causes particle thermal distribution to resist flattening in the aggregate. In simple terms, counter-thermalisation.
I like "as usual"hanelyp wrote:Someone is, as usual, having a problem with comprehension.
Thermalization at low average energy (where collision cross section happens to be larger) is countering thermalization at high average energy. The ions are cycling between regions of high and low kinetic energy. One more effect where the electric potential well is vital to the polywell.