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.
Where Did the Name "Fathom" Come From?
The story behind the Fathom name is intimately tied to the story behind the founding of Applied Flow Technology as a company. So let's go back to 1993. AFT Fathom started as a hobby in 1992 while I was working in the power industry as a research engineer. But it was not named Fathom and I was not planning to start a company. As a hobby, I was plan
AFT Fathom 8 and the Future of AFT
What does all of this mean for the future? The new, more modern look and feel of AFT Fathom 8 is based on a new underlying architecture. We will be working hard to move all of our other products to this architecture as quickly as possible. Our best guess is that AFT Impulse 5 will be available in first quarter of 2013 and AFT Arrow 5 will be avail
The Cool, New Features Coming Soon in AFT Fathom 9
Graphing Let me start by talking about my favorite new feature in AFT Fathom 9. Namely, the new graphing capabilities. Here is a summary of what to expect: Multiple graphs can be displayed concurrently in various forms including stacking and tiling Graphs are persistent and automatically updated when the model is modified Graphs can be generated a
AFT Fathom District Heating Application
In district heating projects, hot water is the most commonly used heating medium. In order to ensure the user's heat load requirements, it is necessary to analyze and calculate the flow balance of the entire district heating system to ensure that different cases can meet the requirements of end users. AFT Fathom is practical fluid dynamic simu
Using Orthogonal Pipe Drawing in AFT Fathom 7.0
A new feature in AFT Fathom 7.0, orthogonal pipe drawing automatically inserts an intermediate vertex into a pipe and adjusts the length of the pipe segments to create a right angle graphical bend between the pipe end points. Orthogonal drawing can be turned on either from Options, Workspace Preferences Display Options tab, or quickly toggled on an
AFT Fathom 8...Worth the Wait
We at Applied Flow Technology are really excited about the new version of AFT Fathom 8 coming in September. Once our customers get their hands on it we are confident they will be equally excited. This version represents the most significant upgrade since AFT Fathom 4 was released in year 2000. It will further establish AFT Fathom as the world's lea
Using Three Way Valves in AFT Fathom
AFT Fathom provides a Three Way Valve which increases the Engineer’s capability to model system control. The Three Way Valve Properties Window shows the three connecting pipes in drop-down lists, which allows users to specify which pipe is the combined flow pipe, and which two are the split flow pipes. By entering the loss profile through each flow
New & Improved Laminar & Non-Newtonian Flow Calculations with AFT Fathom 8
AFT Fathom 8 has a new and improved method for predicting system pressures that involve laminar flow or non-Newtonian fluids. The Adjusted Turbulent K Factor (ATKF) method is used to apply corrections to pipes and components involving these special flows. The ATKF method can be enabled on the System Data tab in the System Properties window. Click
AFT Fathom Smooths Earthquake Impact From California's San Andreas Fault
Ray Hamilton of AMEC made a fascinating presentation of his work using AFT Fathom on the Elizabeth Tunnel at the AFT Denver User Group meeting earlier this month. He went so far as to compare AFT Fathom predictions to those made a century ago by water engineers using slide rules, pencil and paper. Even more fascinating is that his presentation coi
Getting that Stubborn AFT Fathom Model to Converge
The majority of steady-state, incompressible hydraulic models made in AFT Fathom that we see as Applications engineers typically converge very rapidly. However, every once in a while, that occasional AFT Fathom model arrives in our Support inbox that just won’t converge. At first glance, passing a graduate level course in compressible flow without
Using Equivalent Lengths in AFT Fathom
One of the new features in AFT Fathom 9 was the ability to model equivalent lengths instead of K factors for various types of fittings. Since AFT Fathom's existence, the standard K factor loss models have been used to quantify the pressure losses across a fitting such as an elbow, a valve, etc. One of the reasons why the K factor method is ve
Putting Out Fires with AFT Fathom's NFPA Calcs & GSC
If you are performing a hydraulic analysis on your fire system, chances are high that you are working hard and maybe scratching your head in order to adhere to the NFPA codes. The good news is that you can streamline the calculations outlined in the codes with AFT Fathom! NFPA 15 is the standard for fixed water spray systems that are used in
Bring the Heat: Modeling Heat Transfer in Heat Exchangers in AFT Fathom and AFT Arrow
Heat exchangers are some of the most expensive pieces of process equipment, so it is crucial that their pressure losses and heat transfer are well understood. AFT Fathom and AFT Arrow allow users to model heat exchangers within their piping systems. Pressure loss models include input K factors, resistance curves, or tube bundle information. When en
Let the Heat Flow: Modeling Heat Transfer in Pipes in AFT Fathom and AFT Arrow
Among the many talents of AFT Fathom and AFT Arrow software is the ability to model heat transfer. While a major source of heat transfer is heat exchangers, this blog will address heat transfer that occurs in pipes. First, for the basics: Just what is heat transfer? Well, heat transfer occurs when there is a temperature difference between two objec
Reaching Equilibrium: System Energy Balance in AFT Fathom and AFT Arrow
AFT Fathom and AFT Arrow both have the powerful ability to model heat transfer in pipes and heat exchangers, allowing you to represent these critical features of temperature-sensitive systems in your hydraulic model. However, without being able to see the affect heat transfer has on an entire system these features would be of limited usefulness. On
We Have Some Really Kewl New Stuff For You in AFT Fathom 10!
We at AFT work hard. Why?We put a lot of thought into our software features. Why?We try hard to listen to what you, our customers, tell us you want. Why?The answer to all three questions is the same... Excel Data We want to make your life easier. All of you are busy and anything that can make your life easier should be on your
Fathom 11 New Features at a Glance
Recently AFT announced our new release of Fathom 11. With our new release we have been working hard to create a more robust and faster version of Fathom. Along with improved performance we have added several new tools that have been requested by customers. Here is a quick summary of the top 5 new features that you can look forward to in Fath
AFT Fathom 12 New Features are Here
New versions of AFT Fathom, AFT Arrow, and AFT Impulse are being released in the upcoming months. This round of releases focuses on major interface changes which will improve user efficiency. Check out these new features and improvements that will be in Fathom 12, Arrow 9 and Impulse 9. Analysis SetupTo make the modelling process simpler
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
The Opposite of Good Vibrations - Evaluating FIV, AIV, FIP Guidelines from AFT Fathom and AFT Arrow
Learn how to use AFT Fathom and AFT Arrow to help calculate the Likelihood of Failure (LOF) for Flow Induced Vibration (FIV), Acoustic Induced Vibration (AIV), and Flow Induced Pulsation (FIP) in accordance with Energy Institute Guidelines to avoid vibration induced fatigue failure. Introduction to Vibration Induced Fatigue and Failure Repeat
Rockets are Pumping Systems Too - The Aerospace Heritage of AFT
Jeff and I worked together at General Dynamics Space Systems Division in San Diego, California in the late 1980's and early 1990's. I worked there from 1986-1992 on cryogenic rockets on what came to be known as the Atlas I, Atlas II, Atlas IIA and Atlas IIAS. These Atlas rockets had an Atlas booster rocket which was fueled by room temperature RP-1
The First Visual Software for Windows Released 20 Years Ago This Month
AFT Fathom was released commercially twenty years ago this month on April 12, 1994. The history of how AFT Fathom was named is interesting in its own right and was discussed here - Where Did the Name "Fathom" Come From? The list of commercial software “firsts” for AFT Fathom is long and impressive. Here is a summary of some of the more important o
AFT Arrow Turns 20 This Month - the Behind the Scenes Story
Eventually I gave up looking for published methods and set it aside to focus on AFT Fathom 2.0 - which was released in early 1995. I then spent the summer of 1995 focused on developing my own methods for compressible flow. I remember at one point spending six straight weeks reviewing compressible flow textbooks and papers and filling up pads of pa
Calibrate Your Pipeline Using GSC
What is GSC? GSC stands for Goal Seek and Control and is an add-on module for both AFT Fathom and AFT Arrow that automates the search for input parameters to achieve desired output. In other words, it allows the user to define a set of model input variables that are changed until a set of output goals are reached. The first step toward calibrating
Calibrating Your Hydraulic Model with Multiple Data Sets
There are several advantages to calibrating a model to multiple data sets. The primary advantage is of course the increased level of confidence you can have in your model calibration, especially if you use pressure and flow data from the system while it is operating in different configurations (i.e, with different valve positions, different
Iso love the new Pipe Drawing Mode!
There are three Pipe Drawing Modes available on the Arrange menu: 2D Freeform, 2D Orthogonal, and Isometric. Figure 1: Pipe Drawing Modes available on the Arrange menu Figure 1 shows the differences between the three Pipe Drawing Modes. The 2D Freeform mode will place a pipe on the Workspace as drawn. The 2D Orthogonal mode will segment the pipe o
Get More Flexible With Your Fluids
Here at AFT we are always looking for more ways to bring more convenience and accuracy to our model files. One of the ways we are doing this is with NIST REFPROP, the new fluids database that we have incorporated into AFT Fathom 10 and is coming soon in AFT Arrow 7 and AFT Impulse 7. Unlike Chempak, REFPROP is included at no additional cost to
Not a Leak! Modeling Multi-stage Pumps with Discharge Flow Between Stages
AFT Fathom has long included the ability to model multi-stage pumps by representing them with an overall effective pump curve. New in AFT Fathom 10 is the ability to model "Interstage Bleed" or "Takeoff Flow" in these multi-stage pumps. It is well known that arranging pumps in series has the effect of increasing the available head at a
And, Not, Or - Starting Transient Events with Complex Logic
AFT Fathom XTS and AFT Impulse have long been able to start events like pump trips or valve closures when a certain condition is met in the system. For example, a valve can close when a tank is full, or a pump can trip when the flow is too low. However, complex systems often have multiple conditions that can cause an event. The pump may trip when t
Save Money, Reduce Energy and Improve Sustainability with AFT
The growing emphasis on sustainable business practices and environmental responsibility has impacted AFT software in several areas. In recent years we have added built-in capabilities to AFT Fathom and AFT Arrow to calculate energy usage and to estimate the cost to operate rotating equipment. This is available on the Analysis menu in the “Cost Sett
AFT Around the World
In early October, I conducted a 5-day training seminar in Lima, Peru. There were seven different companies represented from Peru and Chile. It is always interesting to see the variety of applications for AFT software and Peru was no exception where many of the engineers are involved in mining operations. Peru is a leading producer of copper, gold,
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
Model Pump Curve Families With Multiple Pump Configurations
You've probably modeled pumps using curve data from the manufacturer. In conjunction with specifying a name reflecting the pump make and model and saving pumps to your component database, selecting and using these pump junctions in your system models is fast and easy. Often, however, a make/model pump will have not one set of head/pressure, efficie
How to Fill as Quadratic
Filters and screens impose a pressure drop that varies with flow rate. The variation is non-linear, but manufacturers will often provide only one data point for pressure loss at the design flow rate. Using a single point, or constant pressure drop, can produce significant inaccuracies in your model. With this in mind, AFT offers the “Fill As Quadr
Automatic Renumbering
All of the pipe numbers in Fathom must be unique. When adding a pipe to a model, the new pipe number will be incremented based on the highest pipe number currently in the model. For example, you may only have 25 pipes on the workspace, but if the highest pipe number is 100, a new pipe will automatically be assigned number 101. After several iterati
Where Did the Name "Arrow" Come From?
There is a similar story behind the naming of AFT Fathom™ and I told that story several months ago in my post entitled Where did the Name Fathom Come From? The story behind the Arrow name is rooted in the beginnings of Applied Flow Technology as a company. So let's go back to 1995.AFT Fathom was released in early 1994. While interest was immediate
New Prices for Next Generation of AFT Software Products
Many of our products have had no price increases for five or even ten years. Further, we will be bundling modules into AFT Fathom 8 and AFT Arrow 5 which in the past were offered at extra cost. US customers can see the new pricing. International customers should contact their distributors for new pricing information. Second and additional licenses
Increasing Heat Exchanger Accuracy for Large Temperature Differences and Non-Linear Heat Capacity
Many times when modeling heat transfer using heat exchangers in AFT Fathom, significant temperature differences across the heat exchanger can have a major impact on the accuracy of the heat transfer results. This can especially become a problem with non-linear heat capacity relationships. The heat transfer across the heat exchanger in t
Annotation Images
One of the many new features in Fathom 8 is the ability to show images in the annotation box. This simple feature will allow the engineer to easily and clearly communicate a vast array of information through the Workspace and Visual Report. To add an image to the Workspace or Visual Report, as seen above, select the Annotation tool from the
What do NASA, DuPont, GDF Suez and the University of Arkansas know about AFT software that you may not? Watch it here!
DuPont The first story talks about how AFT Fathom helped DuPont solve a serious operational problem in three newly designed slurry systems. I co-authored a technical paper along with DuPont's Dan Wood to describe this to industry. AFT Impulse Video NASA The second story is about how AFT Impulse has been used by engineers at NASA's Kennedy Sp
Balance Energy At Junction … What?
AFT Fathom has the ability to model heat transfer. The default mode (found in system properties) is “Constant Fluid Properties”. To avoid confusion in the default mode, several of the heat transfer input fields and option boxes are invisible or disabled until one of the following heat transfer modes are employed: Heat Transfer With Energy Bal
Easily Model Multiple Pump Configurations with ONE PUMP!
AFT Fathom 8 can be used to quickly and easily model multiple pump configurations with different pump speeds and impeller sizes. First, determine a particular pump curve to use from either a manufacturer’s pump curve or pump curve verification test data. Next, determine new pump curves for head and flow using the affinity laws consideri
Default Model Input
The ability to specify default input parameters is a feature that is common to all AFT software products. Diameter, Friction Model, and Design Factors can be specified by default for pipes. Input properties for Junctions are specific to each junction type, so the only common default property is elevation. The default input options are found in “Par
Why You Should Care About AFT's New User Groups
If you answered yes to any of the above, you may want to look into attending an AFT User Group meeting. Last October we held our first User Group meeting in Houston. We had 24 attendees. The consensus was that there was a desire among AFT software users that User Group meetings be held regularly. As a result, we have another Houston User Group me
Modeling Area Changes As Additional Pipe Fittings
If you have a system where there are several area changes throughout the piping, modeling every single area change and connecting pipe can become taxing and time consuming. Also, the more pipes and junctions that are in a model, the higher the complexity. With AFT software, it is very simple to include the area change losses in the pipes them
Coming Soon To a Computer Screen Near You: AFT Impulse 5 - Act Now To Get New Features at Old Prices
Want to know what new features are coming? Read on! Waterhammer Modeling of Slurry Pipe Flow AFT Impulse 5 will offer a new add-on SSL module for modeling slurry flow in piping systems. Why is this important? The AFT Impulse 5 SSL module will offer the first commercially available waterhammer modeling of settling slurry piping systems. The slur
Who Cares About the Surge in "Funny" Fluids?
Funny, non-Newtonian fluids are often broken into two categories: Homogeneous fluids which encompasses non-settling slurries where the fluid and solids behave in an aggregate, homogeneous manner Heterogeneous fluids which encompasses settling slurries where the fluid and solids behave somewhat independently The applications where non-Newtonian fl
Use Control Valve Junctions to Size Valves and Orifice Plates
AFT Fathom can EASILY size valves AND orifice plates with a SINGLE Control Valve junction! There is no need to perform strenuous hand calculations to determine a valve Cv or an orifice diameter. Just specify the system boundary conditions, pipe input properties, and the desired flow rate (or pressure) and AFT Fathom will calculate the C
Model Specialty Valves Accurately with AFT Impulse 5
Applied Flow Technology is proud to release a new version of AFT Impulse, now at version 5. AFT Impulse 5 encapsulates all of the new interface and navigational enhancements from AFT Fathom 8, as well as a considerable breadth of new and improved technical features. One such feature is our newly enhanced Relief Valve Junction. A relief valve can st
From There to Here - The History of AFT Impulse Up Through the New Version 5
From the very beginning AFT Impulse was a world leader. AFT Impulse was first released in November, 1996 which made it the first visual, drag-and-drop waterhammer modeling software for Microsoft Windows (see below). AFT Impulse 1 in 1996 - the First Graphical Waterhammer Software for Windows Those of you who are familiar with AFT Impulse today a