This post attempts to explain an issue when working with Femap and Nastran that might be helpful. If you have landed on this page from a search, then you have likely received the following message from Simcenter Nastran via Femap or by inspecting the f06 file on a failed solution…
TLDR: Compressive loads/stresses within any long, thin structure can cause structural instabilities known as buckling. Buckling occurs when deflections continue to increase even if load is not. This stability analysis is a key component of structural analysis. This article attempts to provide insight for the appropriate buckling factor of safety…
Most of the time you don’t want to model the minutia of bolts, washers, nuts, etc from your imported parts and assembly files. If the part names come across upon import, the labels “MS”/ “NAS”/ “AN” standard hardware may clue you into what to remove from Geometry under the Model…
I wanted to share a quick tip on creating sine/sinusoidal functions in Femap. Some people set these up in Excel first and paste them in from the clipboard, but this will explain how to avoid using that second program. We’ll be setting up functions to describe the time history of…
A somewhat confusing situation can occur when looking at the failure index of composite laminates with thermal loading. You may look at ply by ply strain results and compare that to the ply failure strain you provided on the laminate property entry (PCOMP). For a failure criteria such as Max…
Update for 2022. The capabilities of both these tools continues to evolve, and this post is showing signs of aging. Do not count this unmaintained post as truth, but it can still be a starting point for discussions with resellers of these products. Update for 2019. The Simcenter branding has…
An explanation is required to understand what Femap’s Analysis Monitor is telling you for SOL106: Basic Nonlinear solutions. Specifically, the “Load Step Convergence” option shown below. Note the circled quantities. They’ll be part of the explanation for this example. The convergence ratio is showing the trend of each iteration’s convergence…
This came across my desk today. Sometimes you may need to set up a linear buckling solution that accounts for effects of preload. The simplest example is the crushing of a pressurized soda can. The pressure is constant, but the external load compressing the can may vary, and perhaps you…
Sometimes as a programmer, you want to know the minimum set of instructions/ commands needed to enable some functionality. Well I’ve gone ahead and assembled that for saving custom output data to your Femap model. Here’s a snippet of code that will place custom data into your model. Note that…
Just FYI, there is the forum resource available to those with questions regarding Femap. Normally such questions can be submitted to your reseller (like Structures.Aero), but for those either using an educational grant license or who want to get a response direct from Siemens employees can post here: The forum…