Part 1 of our Wind Load Series “Wind load” is a calculated value representing the total force on a structure or object cause by pressure from wind moving over it. In this blog series, we will discuss different methods for wind load calculations, the factors that influence its magnitude, and the effects a high wind load can have on a structure. Wind load is most commonly addressed by civil and structural engineers when designing buildings, but mechanical engineers can encounter the effect when designing tall objects like cranes, telescoping communications masts or wind turbine towers. Wind Load Essentials As a force, wind load is the product of pressure distributed over an area (psf times ft2 or Pa times m2). In [...]
Figure 1: Simplified model of an aluminum-glass window In last week’s blog, Thermal Expansion in a Glass and Aluminum Window: Part 1, we introduced the basic concept of thermal expansion in solid materials. Since CTE mismatch can impose extremely high stress, during mechanical engineering design one must consider the temperature exposure and expansion or contraction of a material. In order to help the read gain insight, we used a simplified aluminum-framed window to demonstrate that a hot summer day would be enough to shatter glass if the window wasn’t equipped with a flexible gasket between the frame and the glass. For this entry, we utilize a finite element analysis (FEA) to elucidate the stress effects caused by both high and [...]
Equipment designers must accommodate thermal expansion (CTE)of dissimilar materials, especially when they are subject to large temperature changes. This problem is often called "CTE mismatch." In this blog, we give the fundamentals of thermal expansion calculations used in thermo-mechanical analysis. These calculations are simple but useful, and easy enough to perform by hand or with a spread sheet. For more complicated shapes, one must use computer modeling. As an example, we perform a finite element analysis (FEA) in a later blog http://glewengineering.com/thermal-expansion-in-a-glass-and-aluminum-window-part-2/, of a glass and aluminum window and frame to show where the stress is excessive. This points to the obvious need for a gasket to perform as a thermal interface material, in order to lessen [...]
Figure 1: Shear stress results for our concrete slab simulation. The red area of high compression is where the corner of the square-shaped supporting column holds up the slab. © Glew Engineering Consulting, 2016 Welcome to the final entry in our finite element analysis (FEA) blog series, in which I'll discuss a little about analyzing and evaluating FEA results. Over the course of this blog series, I've covered tips on setting up the model in CAD and in the FEA program, configuring the analysis, and generating results. The final step in the process is the analysis of the results, both to get the answers to whatever problem inspired the FEA simulation and to ensure that the final results are [...]
Figure 1: Displacement results for our concrete slab simulation. The slab is supported in the center by a square column, and on the sides by a theoretical wall. © Glew Engineering Consulting, 2016 Time now for the last in our blog series on FEA. I’ve previously discussed how to set up CAD for FEA, how to mesh that CAD model and the different types of analysis that FEA programs can run. The next step in the process is generating results from the FEA simulation, like the displacement illustration in Figure 1. These are fantastic tools for generating useful reports, and are also very useful in helping an FEA consultant or engineer check the accuracy of the own results. As a [...]
Figure 1: Mesh, loads and constraints, ready for analysis © Glew Engineering Consulting, inc. 2016 Welcome again to our series on finite element analysis (FEA). In the last blogs, I covered steps on setting up a computer-aided design (CAD) model and how to set up the mesh and boundary conditions, the most crucial steps in FEA simulation. In this blog, I’ll look at the actual simulation and analysis, which can be the most time-consuming stage in the process. As a reminder, for an example I’ve been using a recent project we worked on involving punching shear in reinforced concrete. We were examining the effectiveness of reinforcing a column-supported concrete slab against the possibility of that column punching through the concrete. Types of [...]
We'll continue on now with our blog series on finite element analysis (FEA). After discussing how to best set up a computer-aided design (CAD) model for FEA simulation, in this blog I'll cover the next step: meshing the model and applying boundary conditions. "Meshing" is the process by which the CAD model is separated into discrete finite elements; it can be done in the same program that runs the FEA numerical simulation later, or it might be performed in a standalone program, depending on your software. Boundary conditions are the loads (forces, movements, impacts, etc) and constraints that interact to actually cause deformation and stress in each element, and in turn the model as a whole. Mesh Generation The mesh essentially [...]
Figure 1: Reinforced concrete mesh © Glew Engineering Consulting Welcome back to our blog series on FEA. In the last blog entry, we introduced some of the fundamental concepts in finite element analysis (FEA). This entry in the blog series focuses on the initial steps in preparing a computer-aided design (CAD) model ready for use in an FEA program. Since FEA programs are very sensitive to the data they have to work with, it's important that the CAD models being analyzed are compatible with the analysis methods the FEA program uses. In order to illustrate my points throughout the blog series, I will introduce a recent FEA consulting project that we completed. Modeling Punching Shear in a Concrete Slab We were recently approached by an academic, who was examining [...]
Figure 1: FEA mesh and shear stress results for a reinforced concrete slab © Glew Engineering Consulting, 2016 Finite Element Analysis Consulting (FEA) In this series of blogs on FEA, we will first cover some basic elements common to many FEA projects, and then in subsequent blogs in this series, illustrate those methods through examples. One of the services that Glew Engineering Consulting provides is finite element analysis consulting (FEA). FEA consulting has been a great boon to the engineering profession, allowing mechanical engineers and civil engineers to accurately model the stress and strain behavior of complicated parts and assemblies prior to building physical prototypes. FEA programs are capable of predicting the effects of loads and impacts, variations in temperature, changes in pressure, and [...]
The value of computational fluid dynamics simulation software, and how it can be useful to an engineering firm.
Discussion related to mechanical engineering of athletic equipment utilizing CAD and FEA
Discussing the engineering constraints, thermal management, and design ideas for chuck heaters used within the semiconductor process.
A discussion of utilizing CFD and FEA to perform stress analysis and thermal analysis on turbines that acquire geothermal energy.
Finite Elemental Analysis (FEA) of Elastometric Materials used in the development of a medical device
Electronics Cooling presenting synthetic jets. Part of a series on different types of electronics cooling and thermal management methods.
Discussing the engineering of hydroelectric energy and the roles played by mechanical engineers and electrical engineers using CAD and FEA as tools.