{"id":11184,"date":"2020-03-09T09:18:19","date_gmt":"2020-03-09T13:18:19","guid":{"rendered":"https:\/\/blogs.sw.siemens.com\/simcenter\/?p=11184"},"modified":"2026-03-26T06:45:53","modified_gmt":"2026-03-26T10:45:53","slug":"rotating-systems-tuning-your-intuition","status":"publish","type":"post","link":"https:\/\/blogs.sw.siemens.com\/simcenter\/rotating-systems-tuning-your-intuition\/","title":{"rendered":"Rotating systems &#8211; Tune your intuition"},"content":{"rendered":"\n<p><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Some fundamentals on the physics of rotation <\/h2>\n\n\n\n<p>Usually, dynamics of rotating systems are taught in Universities, only in third semester of mechanical engineering or physics, after at least two semesters of statics and dynamics. Some of the math involved might look intimidating at first, but the underlying principles are fundamental and influence the design of many technical systems, which we so heavily rely on. <\/p>\n\n\n\n<p>Examples?    Pumps,  WindTurbines, PowerPlants, Transmissions, Machine Tools,  etc. <\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"684\" src=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Rotating_applications-1024x684.png\" alt=\"examples of rotating systems\" class=\"wp-image-11353\" srcset=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Rotating_applications-1024x684.png 1024w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Rotating_applications-600x401.png 600w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Rotating_applications-768x513.png 768w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Rotating_applications-1536x1026.png 1536w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Rotating_applications-2048x1368.png 2048w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Rotating_applications-1110x741.png 1110w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p>So, let\u2019s try to grapple two effects in rotor dynamics, while mostly skipping both math and semesters of dynamics courses, by means of crisp, educational YouTube videos. \ud83d\ude09<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Gyroscopic Precession<\/strong><\/h3>\n\n\n\n<p>Think of the nacelle of an aircraft jet-engine. Take a moment\nto reflect about this question: <\/p>\n\n\n\n<p class=\"has-text-align-center\"><em><strong>What moments\/torques will the nacelle need to bear, while the aircraft takes off?<\/strong><\/em><\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"419\" src=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Aircraft-1024x419.png\" alt=\"\" class=\"wp-image-11211\" srcset=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Aircraft-1024x419.png 1024w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Aircraft-600x245.png 600w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Aircraft-768x314.png 768w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Aircraft-1110x454.png 1110w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Aircraft.png 1475w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure><\/div>\n\n\n<p>So, did you know that the engine nacelle mounts need to bear\na large amount of <strong><em>lateral<\/em><\/strong> bending moments ?!<\/p>\n\n\n\n<p>The reason is gyroscopic precession. Here you can find a\ngood visual explanation, how it originates:<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"Gyroscopic Precession\" width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/ty9QSiVC2g0?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><\/figure>\n\n\n\n<p>Coming back to a high-rpm aircraft engine: It gets tilted upwards, when the the nose landing gear lifts off. The change in the spin vector shows upwards inducing a moment to cause lateral bending.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"456\" src=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Precession_Aircraft-1-1024x456.png\" alt=\"\" class=\"wp-image-11212\" srcset=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Precession_Aircraft-1-1024x456.png 1024w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Precession_Aircraft-1-600x267.png 600w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Precession_Aircraft-1-768x342.png 768w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Precession_Aircraft-1-1110x495.png 1110w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Precession_Aircraft-1.png 1474w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure><\/div>\n\n\n<h3 class=\"wp-block-heading\"><strong>Coriolis Effect<\/strong><\/h3>\n\n\n\n<p>To understand the dominating wind movement in the northern\nhemisphere, one must understand that there is Force pushing the airstreams\neastwards.<\/p>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-1 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"344\" height=\"250\" data-id=\"11361\" src=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/coriolis-2.jpg\" alt=\"\" class=\"wp-image-11361\"\/><\/figure>\n<\/figure>\n\n\n\n<p>There is this <strong>Coriolis Force<\/strong> ,&nbsp; \u2026 or is there?<\/p>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-2 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"565\" data-id=\"11362\" src=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/no_spoon-1024x565.png\" alt=\"\" class=\"wp-image-11362\" srcset=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/no_spoon-1024x565.png 1024w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/no_spoon-600x331.png 600w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/no_spoon-768x423.png 768w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/no_spoon.png 1050w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n<\/figure>\n\n\n\n<p>See here, what happens, when you observe a movement, while being on a rotating reference:<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"Coriolis Effect | National Geographic\" width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/mPsLanVS1Q8?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><\/figure>\n\n\n\n<p>Keeping track with rotating and non-rotating references, is a tricky one. One needs to consider the Coriolis effect indeed. But try to realize the truth: There is no <strong>additional <\/strong>Force. It is a consequence of relative acceleration and depends on the reference system you are observing in.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Conclusion:<\/strong><\/h3>\n\n\n\n<p>This was just to highlight, how important it is to sharpen one\u2019s intuition.  The two above examples are by no means all there is about the dynamics of rotating systems, as the next figure shows:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"447\" src=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/effects-1024x447.png\" alt=\"\" class=\"wp-image-11215\" srcset=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/effects-1024x447.png 1024w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/effects-600x262.png 600w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/effects-768x336.png 768w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/effects-1536x671.png 1536w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/effects-1110x485.png 1110w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/effects.png 1735w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p>When engineering technical systems, like aeroengines and industrial rotating machinery, there is no way around the math. Luckily, modern tools support engineers in dealing with the physics of rotating systems. <\/p>\n\n\n\n<p>Simcenter 3D Rotors was recently introduced to do exactly that, help to go beyond intuition. Find optimal designs and prevent dynamics issues. Find out more on <a href=\"https:\/\/blogs.sw.siemens.com\/simcenter\/simcenter-3d-2020-1-whats-new\/\" target=\"_blank\" rel=\"noreferrer noopener\">Simcenter 3D<\/a> or visit the <a href=\"https:\/\/plm.sw.siemens.com\/en-US\/simcenter\/mechanical-simulation\/simcenter-3d\/\" data-type=\"link\" data-id=\"https:\/\/plm.sw.siemens.com\/en-US\/simcenter\/mechanical-simulation\/simcenter-3d\/\" target=\"_blank\" rel=\"noopener\">product pages<\/a><\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Rotating systems can be tricky. Learn more in this blog<\/p>\n","protected":false},"author":19650,"featured_media":66574,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spanish_translation":"","french_translation":"","german_translation":"","italian_translation":"","polish_translation":"","japanese_translation":"","chinese_translation":"","footnotes":""},"categories":[1,179],"tags":[63605],"industry":[150,155],"product":[577,499],"coauthors":[1899,8313],"class_list":["post-11184","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news","category-product-updates","tag-rotor-dynamics","industry-energy-utilities","industry-industrial-machinery-heavy-equipment","product-simcenter-3d","product-simcenter-cae-solutions"],"featured_image_url":"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2020\/03\/Rotating_applications-1024x684-1.png","_links":{"self":[{"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/posts\/11184","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/users\/19650"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/comments?post=11184"}],"version-history":[{"count":4,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/posts\/11184\/revisions"}],"predecessor-version":[{"id":66575,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/posts\/11184\/revisions\/66575"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/media\/66574"}],"wp:attachment":[{"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/media?parent=11184"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/categories?post=11184"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/tags?post=11184"},{"taxonomy":"industry","embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/industry?post=11184"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/product?post=11184"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/coauthors?post=11184"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}