{"id":9218,"date":"2021-08-15T09:36:43","date_gmt":"2021-08-15T13:36:43","guid":{"rendered":"https:\/\/www.purdue.edu\/freeform\/me323\/?page_id=9218"},"modified":"2025-09-05T10:03:10","modified_gmt":"2025-09-05T14:03:10","slug":"torsion-shear-stress-strain-and-twist-angle","status":"publish","type":"page","link":"https:\/\/www.purdue.edu\/freeform\/me323\/animations-and-demonstrations\/torsion-shear-stress-strain-and-twist-angle\/","title":{"rendered":"Torsion: shear stress\/strain and twist angle"},"content":{"rendered":"<p><span style=\"font-size: 18pt\"><em><strong>Circular shaft experiencing an axial torque<\/strong><\/em><\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-9219 aligncenter\" src=\"https:\/\/www.purdue.edu\/freeform\/me323\/wp-content\/uploads\/sites\/2\/2021\/08\/Untitled-300x159.jpg\" alt=\"\" width=\"340\" height=\"180\" srcset=\"https:\/\/www.purdue.edu\/freeform\/me323\/wp-content\/uploads\/sites\/2\/2021\/08\/Untitled-300x159.jpg 300w, https:\/\/www.purdue.edu\/freeform\/me323\/wp-content\/uploads\/sites\/2\/2021\/08\/Untitled.jpg 475w\" sizes=\"auto, (max-width: 340px) 100vw, 340px\" \/><\/p>\n<p>A solid, circular cross-sectioned shaft experiences an axial torque <em>T<\/em>, as shown above.<\/p>\n<p><span style=\"font-size: 14pt\"><em><strong>Angle of twist<br \/>\n<\/strong><\/em><span style=\"font-size: 12pt\">The hypothesis used in developing the stress and strain in the shaft is that all points on a cross-section of the shaft experience the same angle of twist. The angle of twist for a section of length L is given by the equation shown below.<\/span><\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" style=\"border: 1px solid #000000\" src=\"https:\/\/www.purdue.edu\/freeform\/me323\/wp-content\/uploads\/sites\/2\/2021\/08\/Untitled-3.jpg\" width=\"289\" height=\"250\" \/><\/p>\n<p>The animation shown below demonstrates the geometry of deformation of the shaft under the load of the torque.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" style=\"border: 1px solid #000000\" src=\"https:\/\/www.purdue.edu\/freeform\/me323\/wp-content\/uploads\/sites\/2\/2021\/08\/torsion_03a.gif\" width=\"467\" height=\"284\" \/><\/p>\n<p>A freeze-frame of the twisting of the shaft is shown below.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" style=\"border: 1px solid #000000\" src=\"https:\/\/www.purdue.edu\/freeform\/me323\/wp-content\/uploads\/sites\/2\/2022\/09\/Screen-Shot-2022-09-13-at-10.50.32-PM.jpg\" width=\"369\" height=\"204\" \/><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-size: 14pt\"><em><strong>Stress distribution on the shaft cross-section<\/strong><\/em><\/span><br \/>\nFor the solid cross-section shaft with material homogeneity on the cross-section, the both the shear strain and shear stress vary linearly with radial position on the cross-section, as shown below.<\/p>\n<p style=\"text-align: center\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" style=\"border: 1px solid #000000\" src=\"https:\/\/www.purdue.edu\/freeform\/me323\/wp-content\/uploads\/sites\/2\/2021\/08\/Untitled-4.jpg\" width=\"249\" height=\"334\" \/><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-size: 14pt\"><em><strong>Stress element for points on the cross-section<br \/>\n<\/strong><\/em><\/span><span style=\"font-size: 14pt\"><span style=\"font-size: 12pt\">For point &#8220;a&#8221; on the cross-section, the shear stress on the <em>x<\/em>-face points in the positive <em>z<\/em>-direction. For point &#8220;b&#8221; on the cross-section, the shear stress on the <em>x<\/em>-face points in the negative\u00a0<em>y<\/em>-direction. The corresponding stress elements for these two points are shown below.<\/span><\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" style=\"border: 1px solid #000000\" src=\"https:\/\/www.purdue.edu\/freeform\/me323\/wp-content\/uploads\/sites\/2\/2021\/08\/Untitled-7.jpg\" width=\"409\" height=\"250\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Circular shaft experiencing an axial torque A solid, circular cross-sectioned shaft experiences an axial torque T, as shown above. Angle of twist The hypothesis used in developing the stress and strain in the shaft is that all points on a cross-section of the shaft experience the same angle of twist. The angle of twist for &hellip; <a href=\"https:\/\/www.purdue.edu\/freeform\/me323\/animations-and-demonstrations\/torsion-shear-stress-strain-and-twist-angle\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Torsion: shear stress\/strain and twist angle<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":10,"featured_media":0,"parent":5074,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"class_list":["post-9218","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.purdue.edu\/freeform\/me323\/wp-json\/wp\/v2\/pages\/9218","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.purdue.edu\/freeform\/me323\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.purdue.edu\/freeform\/me323\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.purdue.edu\/freeform\/me323\/wp-json\/wp\/v2\/users\/10"}],"replies":[{"embeddable":true,"href":"https:\/\/www.purdue.edu\/freeform\/me323\/wp-json\/wp\/v2\/comments?post=9218"}],"version-history":[{"count":6,"href":"https:\/\/www.purdue.edu\/freeform\/me323\/wp-json\/wp\/v2\/pages\/9218\/revisions"}],"predecessor-version":[{"id":16343,"href":"https:\/\/www.purdue.edu\/freeform\/me323\/wp-json\/wp\/v2\/pages\/9218\/revisions\/16343"}],"up":[{"embeddable":true,"href":"https:\/\/www.purdue.edu\/freeform\/me323\/wp-json\/wp\/v2\/pages\/5074"}],"wp:attachment":[{"href":"https:\/\/www.purdue.edu\/freeform\/me323\/wp-json\/wp\/v2\/media?parent=9218"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}