Research Department Plasmas with Complex Interactions

1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11

TET

PRO­FES­SOR IS­MAIL RA­FATOV 

Assoc. Pro­fes­sor Is­mail Ra­fatov from the Phy­sics de­part­ment of METU vi­si­ted TET on 11 March 2015. He pre­sen­ted de­tai­led se­mi­nars on the three dif­fe­rent to­pics of his ex­per­ti­se: (1) Over­view of the main mo­del­ling ap­proa­ches (ki­ne­tic/par­ti­cle, hy­brid, and fluid) for gas di­sch­ar­ge plas­mas, (2) Mo­del­ling in COM­SOL Mul­ti­phy­sics: "Equa­ti­on based" model vs. COM­SOL Plas­ma Mo­du­le and (3) Chaos and pat­tern for­ma­ti­on in low-tem­pe­ra­tu­re plas­mas. In the se­mi­nars the basic mo­del­ling ap­proa­ches for the gas di­sch­ar­ge plas­mas were out­lined. Fi­nal­ly, a de­tai­led ana­ly­sis of spa­ti­al and tem­po­ral pat­tern for­ma­ti­on in a dc dri­ven "bar­ri­er" di­sch­ar­ge sys­tem was pre­sen­ted. In the case of pu­re­ly tem­po­ral oscil­la­ti­ons, a tran­si­ti­on of the sys­tem to chaos through pe­ri­od dou­bling bi­fur­ca­ti­ons cas­ca­de could be iden­ti­fied. Bey­ond the in­iti­al tran­si­ent re­gime, nu­me­ri­cal so­lu­ti­ons re­pro­du­ced the Hopf or Tu­ring-Hopf in­sta­bi­li­ty of the ho­mo­ge­neous sta­tio­na­ry state. The agree­ment bet­ween 1d, 2d, and 3d nu­me­ri­cal si­mu­la­ti­ons and a li­ne­ar sta­bi­li­ty ana­ly­sis (wi­t­hin its range of va­li­di­ty) were also de­mons­tra­ted. The visit was spon­so­red by the Ger­man Re­se­arch Fo­un­da­ti­on in the frame of the trans­re­gio­nal col­la­bo­ra­ti­ve re­se­arch cent­re TRR-87.

Is­mail Ra­fatov