Uncategorized Archives

27Nov 2020 by quantyco No Comments

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

A familiar commercial software can boost engineers productivity to a maximum. The downside is cost, especially for research and education projects. The good news for 2020: We found that some GNU software evolved to user friendly products, suitable for a variety of problems and user knowledge levels. This article outlines our opinions, hints and conclusions regarding FreeCAD, GMSH and Salome Meca open source suftware. Intro 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), solving a fluid-structure simulation using parallel computing maybe, and more... Is there any 'best-of-the-best' software package to do it all? Perhaps yes,…

12Sep 2019 by quantyco No Comments

FEA Nocturne – Time for Change?

FEA and stress analysis, Uncategorized

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. Here we will start from deep technical matters and end up with bright future perspectives. 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…

01Aug 2019 by quantyco No Comments

3 Pressure Relief Devices for Integrity Engineers

Mission Impossible, Uncategorized

Caring about plant integrity is a busy and stressful work. Human psychology is such that maintaining current environment is confused with staying in a comfort zone. Albeit this zone may not be comfortable at all (same outcomes from same contractors, same burden of responsibility and document management, same questionable risk management confidence). If you wish to change this environment, consider the holistic improvement of integrity tasks: 1. Know your Risk Cost and Safety Implications One thing in the back of your mind might be: 'How confident are we about what we do for the equipment integrity and safety'? - an obsessive question. Consider all those people going on site and doing the hard work there. And also - all the resources being spend over a facility life. Looking at the…

28Jun 2019 by quantyco No Comments

What is Gigacycle Fatigue importance for pant operators?

Away from a collision course, Mission Impossible, Uncategorized

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 for the…