{"id":374172,"date":"2024-07-30T09:24:22","date_gmt":"2024-07-30T09:24:22","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/"},"modified":"2024-07-30T09:24:22","modified_gmt":"2024-07-30T09:24:22","slug":"374172","status":"publish","type":"reply","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/","title":{"rendered":"Reply To: Single floating structure Ansys AQWA"},"content":{"rendered":"<p>&lt;p&gt;(1) The regular wave time domain analysis includes the nonlinear Froude-Krylov force and the hydrostiatic force. As shown below, the RAO based reposne is defined, which also depends on the COG position in the time domain.&nbsp; I wonder if the RAO based respones could be closer to the frequency domain results when you use smaller wave amplitudes.&lt;\/p&gt;&lt;p&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/07\/30-07-2024-1722330491-mceclip1.png\" width=\"1194\" height=\"187\" \/>&lt;\/p&gt;&lt;p&gt;(2) The big differences of surge at low frequency for a freely floating structure may be possible, as there is no hydrostatic stiffness for any horizontal motion degrees of freedom (i.e. surge, sway, and yaw).&nbsp;&lt;\/p&gt;&lt;p&gt;(3) Is the additional damping matrix included in your time domain analysis?&lt;\/p&gt;&lt;p&gt;(4) Yes, the outputs of the rotational motion responses are in degree. Their RAOs are in [deg\/m].&lt;\/p&gt;&lt;p&gt;(5) The RAO-Based Response has been explained above.&nbsp; Based on the actual motion responses, the low pass filter is used to have the low-frequency responses. The wave frequency response is the difference between the actual response and the low-frequency response. Please see Aqwa theory manual, Section 13.5.3.&lt;\/p&gt;&lt;p&gt;(6) When the wave amplitude is small, the time domain responses should be close to the frequency domain results of which the small amplitude of motion assumation is applied. The time domain analysis may include some nonlinear effects, such as nonlinear Froude-Krylov force and hydrostatic force, nonlinear wave theory (such as 2nd order Stokes waves) or the second order difference frequency and\/or sum frequency wave forces, and drag forces if defined. They make differences when the wave amplitudes are not small.&nbsp;&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-374172","reply","type-reply","status-publish","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"(1) The regular wave time domain analysis includes the nonlinear Froude-Krylov force and the hydrostiatic force. As shown below, the RAO based reposne is defined, which also depends on the COG position in the time domain. I wonder if the RAO based respones could be closer to the frequency domain results when you use smaller\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/\" \/>\n\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 4.9.10\" \/>\n\t\t<meta property=\"og:locale\" content=\"en_US\" \/>\n\t\t<meta property=\"og:site_name\" content=\"Ansys Learning Forum | Ansys Innovation Space\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"Reply To: Single floating structure Ansys AQWA | Ansys Learning Forum\" \/>\n\t\t<meta property=\"og:description\" content=\"(1) The regular wave time domain analysis includes the nonlinear Froude-Krylov force and the hydrostiatic force. As shown below, the RAO based reposne is defined, which also depends on the COG position in the time domain. I wonder if the RAO based respones could be closer to the frequency domain results when you use smaller\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/\" \/>\n\t\t<meta property=\"og:image\" content=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/07\/30-07-2024-1722330491-mceclip1.png\" \/>\n\t\t<meta property=\"og:image:secure_url\" content=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/07\/30-07-2024-1722330491-mceclip1.png\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2024-07-30T09:24:22+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2024-07-30T09:24:22+00:00\" \/>\n\t\t<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n\t\t<meta name=\"twitter:title\" content=\"Reply To: Single floating structure Ansys AQWA | Ansys Learning Forum\" \/>\n\t\t<meta name=\"twitter:description\" content=\"(1) The regular wave time domain analysis includes the nonlinear Froude-Krylov force and the hydrostiatic force. As shown below, the RAO based reposne is defined, which also depends on the COG position in the time domain. I wonder if the RAO based respones could be closer to the frequency domain results when you use smaller\" \/>\n\t\t<meta name=\"twitter:image\" content=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/07\/30-07-2024-1722330491-mceclip1.png\" \/>\n\t\t<script type=\"application\/ld+json\" class=\"aioseo-schema\">\n\t\t\t{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/forums\\\/reply\\\/374172\\\/#breadcrumblist\",\"itemListElement\":[{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum#listItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\",\"nextItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/forums\\\/reply\\\/374172\\\/#listItem\",\"name\":\"Reply To: Single floating structure Ansys AQWA\"}},{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/forums\\\/reply\\\/374172\\\/#listItem\",\"position\":2,\"name\":\"Reply To: Single floating structure Ansys AQWA\",\"previousItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum#listItem\",\"name\":\"Home\"}}]},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/#organization\",\"name\":\"Ansys Learning Forum\",\"description\":\"Ansys Innovation Space\",\"url\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/\"},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/forums\\\/reply\\\/374172\\\/#webpage\",\"url\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/forums\\\/reply\\\/374172\\\/\",\"name\":\"Reply To: Single floating structure Ansys AQWA | Ansys Learning Forum\",\"description\":\"(1) The regular wave time domain analysis includes the nonlinear Froude-Krylov force and the hydrostiatic force. As shown below, the RAO based reposne is defined, which also depends on the COG position in the time domain. I wonder if the RAO based respones could be closer to the frequency domain results when you use smaller\",\"inLanguage\":\"en-US\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/#website\"},\"breadcrumb\":{\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/forums\\\/reply\\\/374172\\\/#breadcrumblist\"},\"datePublished\":\"2024-07-30T09:24:22+00:00\",\"dateModified\":\"2024-07-30T09:24:22+00:00\"},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/#website\",\"url\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/\",\"name\":\"Ansys Learning Forum\",\"description\":\"Ansys Innovation Space\",\"inLanguage\":\"en-US\",\"publisher\":{\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/forum\\\/#organization\"}}]}\n\t\t<\/script>\n\t\t<!-- All in One SEO -->\n\n","aioseo_head_json":{"title":"Reply To: Single floating structure Ansys AQWA | Ansys Learning Forum","description":"(1) The regular wave time domain analysis includes the nonlinear Froude-Krylov force and the hydrostiatic force. As shown below, the RAO based reposne is defined, which also depends on the COG position in the time domain. I wonder if the RAO based respones could be closer to the frequency domain results when you use smaller","canonical_url":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"BreadcrumbList","@id":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/#breadcrumblist","itemListElement":[{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/forum#listItem","position":1,"name":"Home","item":"https:\/\/innovationspace.ansys.com\/forum","nextItem":{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/#listItem","name":"Reply To: Single floating structure Ansys AQWA"}},{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/#listItem","position":2,"name":"Reply To: Single floating structure Ansys AQWA","previousItem":{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/forum#listItem","name":"Home"}}]},{"@type":"Organization","@id":"https:\/\/innovationspace.ansys.com\/forum\/#organization","name":"Ansys Learning Forum","description":"Ansys Innovation Space","url":"https:\/\/innovationspace.ansys.com\/forum\/"},{"@type":"WebPage","@id":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/#webpage","url":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/","name":"Reply To: Single floating structure Ansys AQWA | Ansys Learning Forum","description":"(1) The regular wave time domain analysis includes the nonlinear Froude-Krylov force and the hydrostiatic force. As shown below, the RAO based reposne is defined, which also depends on the COG position in the time domain. I wonder if the RAO based respones could be closer to the frequency domain results when you use smaller","inLanguage":"en-US","isPartOf":{"@id":"https:\/\/innovationspace.ansys.com\/forum\/#website"},"breadcrumb":{"@id":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/#breadcrumblist"},"datePublished":"2024-07-30T09:24:22+00:00","dateModified":"2024-07-30T09:24:22+00:00"},{"@type":"WebSite","@id":"https:\/\/innovationspace.ansys.com\/forum\/#website","url":"https:\/\/innovationspace.ansys.com\/forum\/","name":"Ansys Learning Forum","description":"Ansys Innovation Space","inLanguage":"en-US","publisher":{"@id":"https:\/\/innovationspace.ansys.com\/forum\/#organization"}}]},"og:locale":"en_US","og:site_name":"Ansys Learning Forum | Ansys Innovation Space","og:type":"article","og:title":"Reply To: Single floating structure Ansys AQWA | Ansys Learning Forum","og:description":"(1) The regular wave time domain analysis includes the nonlinear Froude-Krylov force and the hydrostiatic force. As shown below, the RAO based reposne is defined, which also depends on the COG position in the time domain. I wonder if the RAO based respones could be closer to the frequency domain results when you use smaller","og:url":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/","og:image":"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/07\/30-07-2024-1722330491-mceclip1.png","og:image:secure_url":"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/07\/30-07-2024-1722330491-mceclip1.png","article:published_time":"2024-07-30T09:24:22+00:00","article:modified_time":"2024-07-30T09:24:22+00:00","twitter:card":"summary_large_image","twitter:title":"Reply To: Single floating structure Ansys AQWA | Ansys Learning Forum","twitter:description":"(1) The regular wave time domain analysis includes the nonlinear Froude-Krylov force and the hydrostiatic force. As shown below, the RAO based reposne is defined, which also depends on the COG position in the time domain. I wonder if the RAO based respones could be closer to the frequency domain results when you use smaller","twitter:image":"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/07\/30-07-2024-1722330491-mceclip1.png"},"aioseo_meta_data":{"post_id":"374172","title":null,"description":null,"keywords":null,"keyphrases":null,"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"content","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":null,"og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":true,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"","isEnabled":true},"graphs":[]},"schema_type":"default","schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":null,"robots_max_videopreview":null,"robots_max_imagepreview":"large","priority":null,"frequency":null,"local_seo":null,"limit_modified_date":false,"created":"2024-10-28 16:35:13","updated":"2026-09-06 19:41:26","ai":null,"breadcrumb_settings":null,"seo_analyzer_scan_date":null},"aioseo_breadcrumb":"<div class=\"aioseo-breadcrumbs\"><span class=\"aioseo-breadcrumb\">\n\t\t\t<a href=\"https:\/\/innovationspace.ansys.com\/forum\" title=\"Home\">Home<\/a>\n\t\t<\/span><span class=\"aioseo-breadcrumb-separator\">&raquo;<\/span><span class=\"aioseo-breadcrumb\">\n\t\t\tReply To: Single floating structure Ansys AQWA\n\t\t<\/span><\/div>","aioseo_breadcrumb_json":[{"label":"Home","link":"https:\/\/innovationspace.ansys.com\/forum"},{"label":"Reply To: Single floating structure Ansys AQWA","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/374172\/"}],"acf":[],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/374172","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/reply"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/374172\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=374172"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}