{"id":2654,"date":"2021-07-09T19:50:17","date_gmt":"2021-07-09T10:50:17","guid":{"rendered":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/?page_id=2654"},"modified":"2023-11-14T15:07:04","modified_gmt":"2023-11-14T06:07:04","slug":"blackout","status":"publish","type":"page","link":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/en\/research\/blackout.html","title":{"rendered":"Reentry blackout"},"content":{"rendered":"<p style=\"text-align: left;\"><span style=\"color: #a02438;\"><strong>Mitigation of RF blackout by surface catalysis effect<\/strong><\/span><br \/>\nRF blackout is a phenomenon that cuts-off communication between reentry vehicles and the ground station. Its mitigation measures are required. We focused on the surface catalysis effect of an atmospheric reentry capsule to reduce electron density in the capsule wake, which mitigates RF blackouts. Numerical and experimental demonstrations have been conducted using high-performance computers and large-scale plasma wind tunnels.<strong><br \/>\n<\/strong><\/p>\n<p><img loading=\"lazy\" class=\" wp-image-1855 aligncenter\" src=\"https:\/\/cfml.eng.hokudai.ac.jp\/wp-content\/uploads\/2020\/01\/Dist_NumbDens_e_alt80km_g0_Web-300x136.png\" alt=\"\" width=\"401\" height=\"182\" \/><br \/>\n<img loading=\"lazy\" class=\" wp-image-1856 aligncenter\" src=\"https:\/\/cfml.eng.hokudai.ac.jp\/wp-content\/uploads\/2020\/01\/Dist_NumbDens_e_alt80km_g1_Web-300x136.png\" alt=\"\" width=\"401\" height=\"182\" \/><\/p>\n<p style=\"text-align: center;\">Reduction of electron density near an atmospheric reentry capsule without and with surface catalysis<\/p>\n<p><span style=\"color: #a02438;\"><strong>Mitigation of RF blackout by air-<\/strong><\/span><span style=\"color: #a02438;\"><strong>film effect<br \/>\n<\/strong><\/span>We propose a new method for mitigating RF blackouts using the air-film effect, in which a cooling gas is injected from the surface to form an insulating layer. Coupled simulation with the high-enthalpy flow and electromagnetic wave propagation indicates that this approach is effective for blackout mitigation. We are currently demonstrating air-film technology using a high-performance computer and a large plasma wind tunnel.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-3079 size-medium\" src=\"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.00_number_density_of_e_surface_trim-300x174.png\" alt=\"\" width=\"300\" height=\"174\" srcset=\"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.00_number_density_of_e_surface_trim-300x174.png 300w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.00_number_density_of_e_surface_trim-644x374.png 644w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.00_number_density_of_e_surface_trim-768x445.png 768w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.00_number_density_of_e_surface_trim.png 1500w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-3082 size-medium\" src=\"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.40_number_density_of_e_surface_trim-300x174.png\" alt=\"\" width=\"300\" height=\"174\" srcset=\"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.40_number_density_of_e_surface_trim-300x174.png 300w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.40_number_density_of_e_surface_trim-644x374.png 644w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.40_number_density_of_e_surface_trim-768x445.png 768w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.40_number_density_of_e_surface_trim.png 1500w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/p>\n<p style=\"text-align: center;\">Electron density reduction by air-film<\/p>\n<p><img loading=\"lazy\" class=\"size-medium wp-image-3080 aligncenter\" src=\"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.10_log10EF_10000_trim-300x237.png\" alt=\"\" width=\"300\" height=\"237\" srcset=\"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.10_log10EF_10000_trim-300x237.png 300w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.10_log10EF_10000_trim-644x509.png 644w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.10_log10EF_10000_trim-768x607.png 768w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.10_log10EF_10000_trim.png 1100w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/p>\n<p style=\"text-align: center;\"><img loading=\"lazy\" class=\"alignnone size-medium wp-image-3081\" src=\"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.40_log10EF_10000_trim-300x237.png\" alt=\"\" width=\"300\" height=\"237\" srcset=\"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.40_log10EF_10000_trim-300x237.png 300w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.40_log10EF_10000_trim-644x509.png 644w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.40_log10EF_10000_trim-768x607.png 768w, https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-content\/uploads\/2023\/05\/mfr0.40_log10EF_10000_trim.png 1100w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/p>\n<p style=\"text-align: center;\">Comparison of electric field magnitude of electromagnetic waves by air-film effect<\/p>\n<p><strong><span><span style=\"color: #a02438;\">Related paper<\/span><\/span><\/strong><\/p>\n<ul>\n<li><span>\u00a0Hideto Takasawa, Yusuke Takahashi, Nobuyuki Oshima, and Hisashi Kihara, \u201cExperimental Demonstration and Mechanism of Mitigating Reentry Blackout via Surface Catalysis Effects\u201d, Journal of Physics D: Applied Physics, Vol. 54, No. 22, 2021. 225201(11pp) , DOI: 10.1088\/1361-6463\/abe746<\/span><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Mitigation of RF blackout by surface catalysis effect RF blackout is a phenomenon that cuts-off communication &#8230;<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":2646,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_locale":"en_US","_original_post":"189"},"_links":{"self":[{"href":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-json\/wp\/v2\/pages\/2654"}],"collection":[{"href":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-json\/wp\/v2\/comments?post=2654"}],"version-history":[{"count":7,"href":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-json\/wp\/v2\/pages\/2654\/revisions"}],"predecessor-version":[{"id":3183,"href":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-json\/wp\/v2\/pages\/2654\/revisions\/3183"}],"up":[{"embeddable":true,"href":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-json\/wp\/v2\/pages\/2646"}],"wp:attachment":[{"href":"https:\/\/c-mng.cwh.hokudai.ac.jp\/stl.eng\/Root\/wp-json\/wp\/v2\/media?parent=2654"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}