{"id":653,"date":"2016-06-03T19:11:51","date_gmt":"2016-06-03T17:11:51","guid":{"rendered":"http:\/\/fusion.bsc.es\/?p=653"},"modified":"2016-10-22T13:36:49","modified_gmt":"2016-10-22T11:36:49","slug":"first-computer-simulation-for-a-novel-tokamak-start-up-technique","status":"publish","type":"post","link":"https:\/\/fusion.bsc.es\/index.php\/2016\/06\/03\/first-computer-simulation-for-a-novel-tokamak-start-up-technique\/","title":{"rendered":"First computer simulation of a novel tokamak start up technique"},"content":{"rendered":"<figure id=\"attachment_672\" aria-describedby=\"caption-attachment-672\" style=\"width: 370px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-672\" src=\"http:\/\/fusion.bsc.es\/wp-content\/uploads\/NSTX-U_Cross_Section-e1477135961722-337x400.jpg\" width=\"380\" height=\"450\" srcset=\"https:\/\/fusion.bsc.es\/wp-content\/uploads\/NSTX-U_Cross_Section-e1477135961722-337x400.jpg 337w, https:\/\/fusion.bsc.es\/wp-content\/uploads\/NSTX-U_Cross_Section-e1477135961722.jpg 825w\" sizes=\"auto, (max-width: 380px) 100vw, 380px\" \/><figcaption id=\"caption-attachment-672\" class=\"wp-caption-text\">National Spherical Torus Experiment Upgrade (NSTX-U)<\/figcaption><\/figure>\n<p align=\"justify\">Physicist <strong>Dr Fatima Ebrahimi<\/strong> from the Princeton Plasma Physics Laboratory (PPPL) has carried out <b>first computer simulations to evaluate the efficiency of\u00a0\u00a0a start-up mechanism known as coaxial helicity injection (CHI)<\/b>,\u00a0\u00a0of doughnut-shaped fusion machines such\u00a0as tokamaks. The approach simulated by Dr Ebrahimi\u00a0could also benefit\u00a0devices that use superconducting magnets.<\/p>\n<p><!--more--><\/p>\n<p align=\"justify\">CHI would form part of a greater net of magnetic fields that generate the plasma geometry in order to better confine and drive current in the plasma. The main advantage of CHI is\u00a0the fact that\u00a0it does not\u00a0depend on central solenoids which are\u00a0a technological barrier for current driven fusion devices.<\/p>\n<p align=\"justify\"><b>Dr Ebrahimi<\/b> discovered that in her simulations that\u00a070% of the field lines closed in the inside of the device when CHI is applied, compared with 20% or 30% without CHI, thus improving plasma containment and current drive. <em>&#8220;That is a direct application of the research. But now we also have insight into some basic physical phenomena: what are the physics behind the process of reconnection? How do the lines actually close?&#8221;,<\/em> said Dr Ebrahimi.<\/p>\n<p align=\"justify\">More information can be found <a href=\"http:\/\/www.pppl.gov\/news\/2016\/05\/physicist-fatima-ebrahimi-conducts-computer-simulations-indicate-efficiency-innovative\"><b>here<\/b><\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Physicist Dr Fatima Ebrahimi from the Princeton Plasma Physics Laboratory (PPPL) has carried out first computer simulations to evaluate the efficiency of\u00a0\u00a0a start-up mechanism known as coaxial helicity injection (CHI),\u00a0\u00a0of doughnut-shaped fusion machines such\u00a0as tokamaks. The approach simulated by Dr Ebrahimi\u00a0could also benefit\u00a0devices that use superconducting magnets.<\/p>\n","protected":false},"author":6,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-653","post","type-post","status-publish","format-standard","hentry","category-world"],"_links":{"self":[{"href":"https:\/\/fusion.bsc.es\/index.php\/wp-json\/wp\/v2\/posts\/653","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fusion.bsc.es\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fusion.bsc.es\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fusion.bsc.es\/index.php\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/fusion.bsc.es\/index.php\/wp-json\/wp\/v2\/comments?post=653"}],"version-history":[{"count":15,"href":"https:\/\/fusion.bsc.es\/index.php\/wp-json\/wp\/v2\/posts\/653\/revisions"}],"predecessor-version":[{"id":1172,"href":"https:\/\/fusion.bsc.es\/index.php\/wp-json\/wp\/v2\/posts\/653\/revisions\/1172"}],"wp:attachment":[{"href":"https:\/\/fusion.bsc.es\/index.php\/wp-json\/wp\/v2\/media?parent=653"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fusion.bsc.es\/index.php\/wp-json\/wp\/v2\/categories?post=653"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fusion.bsc.es\/index.php\/wp-json\/wp\/v2\/tags?post=653"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}