{"id":397207,"date":"2024-12-12T08:08:26","date_gmt":"2024-12-12T08:08:26","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/transmit-boundary-reflection-perturbation-of-pressure-waves\/"},"modified":"2024-12-12T08:08:26","modified_gmt":"2024-12-12T08:08:26","slug":"transmit-boundary-reflection-perturbation-of-pressure-waves","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/transmit-boundary-reflection-perturbation-of-pressure-waves\/","title":{"rendered":"Transmit boundary &#8211; reflection \/ perturbation of pressure waves"},"content":{"rendered":"<p>&lt;p&gt;Dear all,&lt;\/p&gt;&lt;p&gt;I am using Ansys Autodyn 2023 R2 to simulate the impact of an energy beam.&lt;\/p&gt;&lt;p&gt;For this simulation I am using an Eulerian mesh, no failure or strength model, and I apply only one boundary condition at the upper radius (0.4mm cf. images) which is &#8220;Transmit (Euler\/Lagrange)&#8221;. All references in the boundary definition are set to zero.&lt;\/p&gt;&lt;p&gt;I do not understand why my pressure wave is disturbed by this boundary condition. Should it not allow the wave to pass through as if the material were continuous?&lt;\/p&gt;&lt;p&gt;Below is a comparison of the results obtained without the boundary condition (total reflection of the wave) and with the transmit condition (creation of a disturbance with a large amplitude).&lt;\/p&gt;&lt;p&gt;How can I solve this problem without enlarging my part?&lt;\/p&gt;&lt;p&gt;Thank you for your help,&lt;\/p&gt;&lt;p&gt;Audrey&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;&lt;p&gt;&nbsp;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/12-12-2024-1733988669-Pressure_cut_the_part_04mm_no_BC_800.png\" alt=\"No_boundary_condition_cycle_800\" width=\"929\" height=\"581\" \/><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/12-12-2024-1733988737-Pressure_cut_the_part_04mm_no_BC_900.png\" alt=\"No_boundary_condition_cycle_900\" width=\"936\" height=\"596\" \/><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/12-12-2024-1733988768-Pressure_cut_the_part_04mm_transmit_800.png\" alt=\"Transmit_boundary_condition_cycle_800\" width=\"934\" height=\"600\" \/><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/12-12-2024-1733989378-Pressure_cut_the_part_04mm_transmit_900.png\" alt=\"Transmit_boundary_condition_cycle_900\" width=\"938\" height=\"591\" \/>&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-397207","topic","type-topic","status-publish","hentry","topic-tag-ansys-autodyn-1","topic-tag-boundary-conditions"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["27814"],"_bbp_topic_id":["397207"],"_bbp_subscription":["286739","58821","83","495729"],"_bbp_author_ip":["2001:1458:202:d6::102:4be3"],"_bbp_last_reply_id":["398193"],"_bbp_last_active_id":["398193"],"_bbp_last_active_time":["2024-12-21 22:32:49"],"_bbp_reply_count":["5"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["4"],"_bbp_engagement":["286739","58821","83","495729"],"_btv_view_count":["249"],"_bbp_topic_status":["unanswered"]},"test":"audrey-piccinicern-ch"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/397207","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/397207\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=397207"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}