<\/p>\n
I can represent quite well the experimental results from the technical document below but I noticed a problem, which I can’t solve :<\/p>\n
<\/p>\n
The boundary condition at the nozzle inlet is a pressure-inlet, with a Gauge Total Pressure of 253 312 Pa (2.5 atm, the pressure I need in my thrust chamber) and a Supersonic\/Initial Gauge Pressure of 250 000 Pa. My operating condition is 0 Pa and my domain outlet is a Pressure-outlet at 101 325 Pa.<\/p>\n
<\/p>\n
When I initialize my solution (Hybrid Initialization), the maximum pressure is at the right value (253 312 Pa) and this pressure is located at the inlet. But when I run my solution and look at the results, the maximum pressure dropped a little bit and the pressure at inlet is not the right one anymore (246 472 Pa i.e. a drop of 6840 Pa). I plotted the pressure at inlet to get the divergence (picture attached<\/em>), it shows that the pressure drop happens at first iteration then stabilize at the unwanted value after 25-30 iterations.<\/p>\n <\/p>\n The thing is I can’t explain this phenomenon. I should be able to keep a fixed pressure value at inlet since this is the pressure-inlet.<\/p>\n <\/p>\n Input parameters:<\/span><\/p>\n <\/p>\n Solver:<\/strong> Steady – Pressure-based – Axisymmetric<\/p>\n <\/p>\n Material:<\/strong> Air (ideal-gas)<\/p>\n <\/p>\n Model:<\/strong> SST k-omega<\/p>\n <\/p>\n Boundary conditions:<\/strong> 1 pressure inlet (2.5 atm), 1 pressure outlet (1 atm)<\/p>\n <\/p>\n Solution method:<\/strong> ROE-FDS – Least square – 2nd order<\/p>\n <\/p>\n Initialization method:<\/strong> Hybrid<\/p>\n <\/p>\n Pictures<\/em><\/p>\n <\/p>\n Domain:<\/strong><\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n Evolution of pressure at inlet:<\/strong><\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n Thanks!<\/p>\n <\/p>\n Killian<\/p>\n","protected":false},"template":"","class_list":["post-42341","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_old_topic_id":["14521"],"_bbp_old_topic_author_name_id":["Anonymous"],"_bbp_old_is_topic_anonymous_id":["false"],"_bbp_old_closed_status_id":["publish"],"_bbp_author_ip":[null],"_bbp_old_sticky_status_id":["normal"],"_bbp_likes_count":["0"],"_btv_view_count":["1131"],"_bbp_subscription":["240687"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["42341"],"_bbp_forum_id":["27792"],"_bbp_engagement":["118","22555","166009"],"_bbp_voice_count":["3"],"_bbp_reply_count":["4"],"_bbp_last_reply_id":["111499"],"_bbp_last_active_id":["111499"],"_bbp_last_active_time":["2020-04-16 19:26:38"]},"test":"killian153"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/42341","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\/42341\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=42341"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"Geometry\"](\"https:\/\/us.v-cdn.net\/6032193\/uploads\/attachments\/b45dcc9b-650f-48b5-bed2-aa6b007b5399\/d28b3192-cf76-4e72-a228-ab90015bfff1_domain.jpg?width=690&upscale=false\")
<\/p>\n![\"Evolution](\"https:\/\/us.v-cdn.net\/6032193\/uploads\/attachments\/b45dcc9b-650f-48b5-bed2-aa6b007b5399\/6e43d8a6-2280-434b-a599-ab90015c4f69_pressure.jpg?width=690&upscale=false\")
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