AFT Blog
Welcome to the Applied Flow Technology Blog where you will find the latest news and training on how to use AFT Fathom, AFT Arrow, AFT Impulse, AFT xStream and other AFT software products.
AFT Arrow & AFT xStream New Features Coming Soon
We recently discussed the new features coming out in AFT Fathom 13 and AFT Impulse 10. Now let's talk about the compressible gas and steam side of the product launches. You may be more familiar with AFT Fathom, as it is our flagship incompressible steady state analysis product. AFT Arrow is its counterpart for compressible steady sta
Resources to Validate AFT Software
Users regularly contact us asking for information to assist them in validating AFT software. The formality of the validation requirement ranges from customer's self imposed internal requirements to rigorous validation as required for work in the nuclear industry. Fortunately, AFT provides extensive reference material for validation and, what's more
Gas and Steam Transient Analysis is Freaking Hard!
Whew! That was a lot of hard work! As of Monday, April 12, 2021, AFT xStream™ is loaded up and ready to go. And to help you simulate things you have only guessed at before.When we engaged Fred Moody a few years ago to teach a short course at AFT that covered compressible gas and steam transients, we were not certain a commercial quality product cou
Having model convergence problems? Start here!
Trying to run a model and running into convergence errors? Here are a few common tips to help with model convergence for AFT Fathom, AFT Arrow, and the steady state modes for AFT Impulse and AFT xStream. Though these tips will not work for all models, they have helped with many of the steady state convergence cases that have come through the AFT s
Get the Most Out of AFT's Fluid Property Viewers
Veteran AFT software users are familiar with heritage products like AFT SteamCalc and AFT Chempak Viewer. Some have wondered where these products went. Although licenses to these products are no longer sold, these viewers are now integrated into the main applications for each of AFT's main products: AFT Fathom, AFT Arrow, AFT Impulse, and AFT
Quick Guide to Custom Output
You've built a model, verified all of the inputs, and now you have results, but how are you going to organize and present these results? Here is a quick guide to some of the customization available in AFT software for displaying output and exporting your data using the Output, Visual Report, and Graph Results windows. The screenshots and examples f
Introducing the AFT Arrow XTS Module!
AFT has some good news for engineers who analyze gas transients. AFT is introducing the new AFT Arrow Extended Time Simulation (XTS) Add-on Module to help engineers better calculate compressed gas flow rate changes in piping systems. This time-based simulation software allows engineers who are designing or troubleshooting industrial
Is there steam on your (Microsoft) Windows? How ASME Steam Tables came to be.
In the modern world there are many things we take for granted – especially in first-world countries. Among them are the reliable availability of water and electricity. To our homes. To our workplaces. Just about everywhere.Engineers also take things for granted. One of those is reliable data on the properties of steam and water. But it was not alwa
For Geeks Only – Solving Transient Compressible Flow Equations
Be forewarned that today I am going into full on geek mode and talk about equations for transient compressible flow. These equations are in the form of hyperbolic partial differential equations (PDEs'). If that did not scare you away yet, then you may be as much of a geek as I am! With some fancy mathematics, three PDE's can be converted into six o
Find Help Faster with the Documentation Portal
AFT strives to make our interface intuitive and user-friendly, but we know that pipe flow modeling can be complex. That's why the AFT team have worked to put together the AFT documentation portal, a new centralized place to find all of our help resources for AFT Fathom, AFT Arrow, AFT Impulse, and AFT xStream. Here's a quick summary of what you can
Get in Control with Control Valves
Having some trouble getting your modelling under control? This blog will discuss some tips on how to properly use a control valve in AFT Fathom and how to interpret some common control valve warnings. For simplicity this blog will primarily discuss control valves in the context of AFT Fathom. However, the concepts discussed in this blog also apply
Don't throw a fit over your Fitting K Factors - Part 1: Fittings & Losses in AFT Fathom
AFT Fathom, AFT Arrow, AFT Impulse, and AFT xStream all have a tab in the Pipe Properties window called "Fittings & Losses" which allows users to quickly specify K factors for components within a pipeline such as valves, elbows, and area changes. The Fittings & Losses allow you to simplify your model and avoid workspace clutter by int
Steam Piping in Nuclear Power Plants Is Not As Safe As Commonly Believed
As if we all need something else to worry about, right? But I am afraid it is true. The concern stems from how fast steam acoustic waves steepen as they transmit through a system. This steepening causes transient forces on the steam piping much higher than conventional methods predict.When I was beta testing AFT's latest software product, AFT xStre
The Truth About Air Compressors
Air compressors, they are a machine that everyone has interacted with in their life time. Whether it is in the garage, at the gas station, or in a manufacturing environment compressed air is everywhere. Compressed air is one of the most widely used utilities out there, but also one of the most expensive utilities out there. The key to is to make su
Would Newton Approve of How You Use His Law?
Improve Safety & Accuracy in Pipe Force Predictions ASME B31 piping code requires engineers to consider loads on pipes from waterhammer, steam hammer and other fluid transients. In principle, this means using Newton's Second Law which he published over three centuries ago. In 1687 to be specific. And in Latin if you want to read it in it
Restore Your Sanity, and Your Corrupted Model Files
Users occasionally contact AFT saying they have lost their model files or cannot open them. Can you imagine spending hours, days, or months building models, and all of a sudden, the progress and work is gone?! If it happens right before a deadline, the engineer will most likely have a minor panic attack, and feelings of anger, depression, or hopele
Declutter Your Natural Gas Model
I don't have any tips for decluttering your garage or office desk, but I can offer you a tip on how to declutter your natural gas model. Perhaps it will save you some time as well in the design phase. As engineers, we like details and will enter as many as possible into our models. I've seen several AFT Arrow and xStream models with natural gas mix
My Recent Visit With Newton and Galileo
I suspect Europeans who live near world history sites just accept this as normal. For a backwater American like me, it is amazing to come across the final resting places of Isaac Newton and Galileo. I recently had that privilege in London and Florence. On my 60th birthday in early April, I had the privilege of visiting Westminster Abbey. Among the
Compressor Maps
A Compressor Map in AFT Arrow allows you to more accurately model the full range of operating conditions for a Centrifugal Compressor junction. AFT recognized the need for this specific feature from customers via support requests and consulting projects. Well, good news…this capability is here! The featu
Reciprocating Compressors and Modeling Approaches
The release of AFT xStream 3 brings with it reciprocating compressors for your gas transient models! Positive displacement compressors now have two subtypes: fixed flow rate for a steady mass or volumetric flow rate, as was present previously, and the all-new reciprocating compressor option. The reciprocating compressor model is for compressors in