{"id":165295,"date":"2023-03-17T08:59:57","date_gmt":"2023-03-17T08:59:57","guid":{"rendered":"\/knowledge\/forums\/topic\/in-a-piezoelectric-analysis-can-the-mutual-energy-um-be-negative\/"},"modified":"2023-07-31T12:30:59","modified_gmt":"2023-07-31T12:30:59","slug":"in-a-piezoelectric-analysis-can-the-mutual-energy-um-be-negative","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/in-a-piezoelectric-analysis-can-the-mutual-energy-um-be-negative\/","title":{"rendered":"In a piezoelectric analysis, can the Mutual Energy (Um) be negative?"},"content":{"rendered":"<p>Yes.  It is mathematically possible for Um to be negative.  For a piezoelectric analysis the energies that have physical meaning are the strain energy (associated with strain distribution) and dielectric energy (associated with electric field distribution).  They are always positive.  The Mutual &#8220;Energy&#8221; is a hybrid value that has no physical meaning but can be useful for some calculations.  It can be positive or negative.  How the energies are calculated is detailed in Chapter 11 of the MAPDL Theory Manual.<\/p>\n","protected":false},"template":"","class_list":["post-165295","topic","type-topic","status-publish","hentry","topic-tag-4706","topic-tag-mechanical-apdl-f-ansys","topic-tag-multiphysics-and-emag-apdl","topic-tag-piezoelectric","topic-tag-structural-mechanics"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"Yes. It is mathematically possible for Um to be negative. For a piezoelectric analysis the energies that have physical meaning are the strain energy (associated with strain distribution) and dielectric energy (associated with electric field distribution). They are always positive. The Mutual &quot;Energy&quot; is a hybrid value that has no physical meaning but can be\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/in-a-piezoelectric-analysis-can-the-mutual-energy-um-be-negative\/\" \/>\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 Knowledge | Ansys Innovation Space\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"In a piezoelectric analysis, can the Mutual Energy (Um) be negative? | Ansys Knowledge\" \/>\n\t\t<meta property=\"og:description\" content=\"Yes. It is mathematically possible for Um to be negative. For a piezoelectric analysis the energies that have physical meaning are the strain energy (associated with strain distribution) and dielectric energy (associated with electric field distribution). They are always positive. The Mutual &quot;Energy&quot; is a hybrid value that has no physical meaning but can be\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/in-a-piezoelectric-analysis-can-the-mutual-energy-um-be-negative\/\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2023-03-17T08:59:57+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2023-07-31T12:30:59+00:00\" \/>\n\t\t<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n\t\t<meta name=\"twitter:title\" content=\"In a piezoelectric analysis, can the Mutual Energy (Um) be negative? | Ansys Knowledge\" \/>\n\t\t<meta name=\"twitter:description\" content=\"Yes. It is mathematically possible for Um to be negative. For a piezoelectric analysis the energies that have physical meaning are the strain energy (associated with strain distribution) and dielectric energy (associated with electric field distribution). They are always positive. 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It is mathematically possible for Um to be negative. For a piezoelectric analysis the energies that have physical meaning are the strain energy (associated with strain distribution) and dielectric energy (associated with electric field distribution). They are always positive. 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It is mathematically possible for Um to be negative. For a piezoelectric analysis the energies that have physical meaning are the strain energy (associated with strain distribution) and dielectric energy (associated with electric field distribution). They are always positive. 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It is mathematically possible for Um to be negative. For a piezoelectric analysis the energies that have physical meaning are the strain energy (associated with strain distribution) and dielectric energy (associated with electric field distribution). They are always positive. The Mutual &quot;Energy&quot; is a hybrid value that has no physical meaning but can be","og:url":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/in-a-piezoelectric-analysis-can-the-mutual-energy-um-be-negative\/","article:published_time":"2023-03-17T08:59:57+00:00","article:modified_time":"2023-07-31T12:30:59+00:00","twitter:card":"summary_large_image","twitter:title":"In a piezoelectric analysis, can the Mutual Energy (Um) be negative? | Ansys Knowledge","twitter:description":"Yes. It is mathematically possible for Um to be negative. 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