27Nov 2020 by quantyco
Freeware CAD and FEA 2020 – Part 1: User friendly options

Freeware CAD and FEA 2020 – Part 1: User friendly options

FEA and stress analysis
Our review of free CAD & FEA software. Contest results of FreeCAD, GMSH and SalomeMeca2019. Explore their features pros and cons for general use cases. We found one absolute winner in this contest. A familiar commercial software can boost engineers productivity to a maximum. The downside is its cost, especially for research and education projects. The good news for 2020: We found that some GNU software has now evolved to user friendly products, suitable for a variety of problems and user knowledge levels.  Intro To begin with, being involved in any kind of engineering, either by profession or as a hobby, you have probably faced the challenge of choosing a CAD software for: making a drawing, preparing a model for your 3D printer, simulating an object for stress analysis (FEA),…
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12Sep 2019 by quantyco
FEA Nocturne – Time for Change?

FEA Nocturne – Time for Change?

FEA and stress analysis
Finite Element Analysis (FEA) is indispensable for visualizing a structural response to a wide spectrum of loads and design options. FEA enables plotting a stress/strain field for complex geometries, which is not feasible to do by hand calculations. It appears that FEA services lose popularity in our industry. Here I share my thoughts why this happened, and conclude on how to improve the FEA practicality and to embed it into the plant asset management process. These tips are for FEA practitioners only. Fig. 1. FEA analysis loop, as it should be Introduction - What is FEA at a glance? Structural Mechanics force, displacement and stress calculations are well suitable for simple, idealized objects like beam frames (steel bridges, tower cranes, scaffolds etc.). Real structures usually have multiple 'complications' like joints…
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28Jun 2019 by quantyco
What is Gigacycle Fatigue importance for pant operators?

What is Gigacycle Fatigue importance for pant operators?

FEA and stress analysis
It is known that the 1st fatigue curve was created in XIX century by German engineer August Woehler. He investigated why railroad carriage axles fail in a delayed manner. The Woehler's phenomenological fatigue model was correct and remains generally valid now. However, there are some additional limitations and improvement ideas, which are necessary for practical vibration fatigue predictions.     Misconceptions first Consider the above graph meaning: The Number of stress cycles to failure (N) is a function of the Stress amplitude in each cycle (S). More stress means less life, as shown by the red line. The yellow line simulates a constant amplitude fatigue limit. Finally, the green line is the variable amplitude stress cut-off, e.g. no fatigue damage is assumed in design for lower stresses. The historical reason…
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22Nov 2017 by quantyco
Is this assessment or design?

Is this assessment or design?

FEA and stress analysis
Equipment integrity design and assessment methods are not only linked to different life stages. These methods are essentially different in their concepts. A strange mixture of design and assessment data can be observed in engineering reports where this difference is misunderstood. Let's find the logic for engineering tools selection from the decision confidence standpoint. The engineering 'Reality' I describe the purpose of engineering activities as understanding and addressing the Reality for a continued safe operation of the equipment. Reality here is the equipment actual load bearing capacity in the environment of real operational loads and damage processes. This is a key element of the design Quality. Otherwise, not controlling the equipment integrity will jeopardize the cost/benefit control aspirations. Once, I was involved in some bidding on a small fitness-for-service (FFS)…
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