Vortex Shedding
Stack Supported on Structure
Stack Supported on Structure April 11 2024 There are many real-world examples of steel stacks or chimneys supported on top of another structure. This could be a space frame, building or another piece of equipment such as a heater. The supporting structure can introduce flexibility to the system, and this article explains how to consider…
Read MoreSteel Stack Deflection
When designing a stack should steel stack deflection be a concern? It’s a good question and one that comes up frequently, The design standards give some guidance, but the standards vary in how they handle steel stack deflection and there is some room for interpretation. Here we discuss the major considerations with regard to stack…
Read MoreAnchor Bolt Pretension
There is nothing simple about recommending anchor bolt pretension, ask ten engineers and you could get eleven different recommendations. Meca has done all of the research in order to try to resolve this topic once and for all…at least until the next anchor bolt pretension recommendation is published. We are definitely not experts on this…
Read MoreAdd Some Guy Wires
Add Some Guy Wires Dec 13, 2019 When and why should I use guy wires on a stack? When a stack has a vortex shedding problem there can be many factors that determine which solutions are the best. Guy wires aren’t always the most conventional solution, but its always an option to consider. How do…
Read MoreSlow Down
Slow Down Nov 8, 2019 I’ll bet “Slow Down” isn’t an expression you hear much in your business. I dream of a day when a customer tells me, “Slow down, we really don’t care when you finish your design.” I can’t get you more time on your deadline, but I can tell you one instance…
Read MoreI Feel the Need, the Need for Speed
I Feel the Need, the Need for Speed Oct 18, 2019 In my humble opinion, the Movie Top Gun is one of the best movies of all time. One of the best parts is when Tom Cruise says “I feel the need, the need for speed”. It’s not just a great line, it also applies…
Read MoreWelcome to our Damping Pad
Welcome to our Damping Pad Sep 19, 2019 When a vortex shedding problem exists on a stack, sometimes the most economical option is a damping pad. What is a damping pad? A damping pad is a preformed laminated fabric pad of a manufactured material composed of layers of tightly twisted, closely woven lightweight material. Each…
Read MoreHow to Determine Damping
How to Determine Damping Jul 26, 2019 We can all grasp the physical attributes of a stack such as the height, weight, diameters, etc.; however, what is the stack’s structural damping? Does MecaStack estimate the damping of the stack? Is there any harm in just arbitrarily changing the damping value? Damping Basics: To answer this question we…
Read MoreGetting Twisted about Helical Strakes
Getting Twisted about Helical Strakes Jun 25, 2019 If you have a vortex shedding problem on a stack, then in some cases helical strakes are your best option; however, there are other cases where helical strakes are not the best option. When not to use Helical Strakes? If there is another stack (or tall structure) that is…
Read MoreTake Vortex Shedding Seriously
Take Vortex Shedding Seriously May 20, 2019 When I was a new Engineer working for an equipment manufacturer, I can say that I didn’t have a healthy appreciation for wind Induced vibration (vortex shedding). I worked for an equipment manufacturer who won and lost jobs based upon our cost, and considering vortex shedding increased our…
Read MoreTune up your next Stack
Tune up your next Stack Apr 5, 2019 One of the most common problems encountered on a cylindrical stack is Wind Induced vibration due to Vortex Shedding. If you have never visually observed vortex shedding, watch this brief video and prepare to be amazed. There are a couple of options to address this problem, and this newsletter…
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