{"id":391808,"date":"2024-10-29T16:49:11","date_gmt":"2024-10-29T16:49:11","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/391808\/"},"modified":"2024-10-30T15:13:46","modified_gmt":"2024-10-30T15:13:46","slug":"391808","status":"publish","type":"reply","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/391808\/","title":{"rendered":"Reply To: Thermal Analysis of Sealed Cabinet"},"content":{"rendered":"<p>&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;Hi,&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;Thanks for contacting us.&nbsp;When you encounter memory issues in LS-DYNA, especially with limited memory resources, there are several ways to optimize your simulation for more efficient memory use, which are outlined below:&lt;\/span&gt;&lt;\/p&gt;&lt;h3&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>&ndash; Reduce the Element Count<\/strong>&lt;\/span&gt;&lt;\/h3&gt;<\/p>\n<ul>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>Mesh Optimization<\/strong>: Use a coarser mesh in regions where high accuracy is not crucial and apply a finer mesh only in areas of interest (e.g., stress concentration zones). This reduces the memory needed to store and compute element data.&lt;\/span&gt;<\/li>\n<\/ul>\n<p>&lt;h3&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>&ndash; Use a Single Precision Version of LS-DYNA<\/strong>&lt;\/span&gt;&lt;\/h3&gt;<\/p>\n<ul>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>Single Precision Solver<\/strong>: Run the solver in single precision if double precision isn&rsquo;t required for your application. Single precision uses half the memory of double precision and can still yield good results, especially for non-high-accuracy simulations.&lt;\/span&gt;<\/li>\n<\/ul>\n<p>&lt;h3&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>&ndash; Optimize Contact Definitions<\/strong>&lt;\/span&gt;&lt;\/h3&gt;<\/p>\n<ul>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>Simplify Contact Types<\/strong>: Use simpler contact definitions where possible. For instance, *CONTACT_AUTOMATIC_SINGLE_SURFACE consumes more memory than *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE. Only use the former if absolutely necessary.&lt;\/span&gt;<\/li>\n<\/ul>\n<p>&lt;h3&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>&ndash; Reduce Output Frequency<\/strong>&lt;\/span&gt;&lt;\/h3&gt;<\/p>\n<ul>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>Database Output<\/strong>: Lower the output frequency of results files like D3PLOT and GLSTAT, which consume a lot of memory and disk space. For example, change from every 0.1 ms to every 1 ms if appropriate.&lt;\/span&gt;<\/li>\n<p>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>Selective Output<\/strong>: Disable unnecessary outputs, or only save variables critical to the analysis. For example, avoid saving stress and strain at every time step if they are not essential.&lt;\/span&gt;<\/li>\n<\/ul>\n<p>&lt;h3&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>&ndash; Run on Fewer Processors<\/strong>&lt;\/span&gt;&lt;\/h3&gt;<\/p>\n<ul>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>Processor Adjustment<\/strong>: Running on too many processors with limited memory can lead to memory fragmentation and increased demands. Try reducing the number of processors to optimize memory use, especially on machines with limited cores and RAM.&lt;\/span&gt;<\/li>\n<\/ul>\n<p>&lt;h3&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>&ndash; Simplify Element Types<\/strong>&lt;\/span&gt;&lt;\/h3&gt;<\/p>\n<ul>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>Switch to Simpler Elements<\/strong>: If your model allows, use simpler elements (e.g., reduce higher-order elements to linear elements) to cut down on memory use.&lt;\/span&gt;<\/li>\n<\/ul>\n<p>&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;If you continue to experience difficulties, it may be beneficial to consult the LS-DYNA user documentation or reach out to Ansys support for more targeted advice on managing memory usage for your specific simulation scenario.&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;Thanks,&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;Pedram&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-391808","reply","type-reply","status-publish","hentry"],"aioseo_notices":[],"acf":[],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/391808","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":6,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/391808\/revisions"}],"predecessor-version":[{"id":392043,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/391808\/revisions\/392043"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=391808"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}