Dynamic solutions for a fluid world™

AFT Blog

Welcome to the Applied Flow Technology Blog.
Trey Walters

Shhhh! Suppressing Sound Waves From Rocket and Space Shuttle Engines

In case you have not noticed, rockets can be really loud. Sound suppression on vertically launched rockets (and the Space Shuttle, back when it was flying) is more important than most of you would think. And for a different reason than most of you would guess.

Every so often I get to talk about my first job which was in the aerospace industry where I first learned about sound suppression systems. Today AFT software is used on several of these systems by our customers in the aerospace industry as well as NASA. 

The flowrate of water used in the sound suppression process is enormous. Which is why they are often called "deluge systems".

Continue reading
  1047 Hits
  0 Comments
Abby Zimmerman

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 energy balances are being considered, users can choose between 11 heat transfer models in AFT Fathom and 12 heat transfer models in AFT Arrow to best meet their hydraulic modeling needs. While AFT Fathom and AFT Arrow can also model heat transfer in pipes ,...
Continue reading
  1086 Hits
  0 Comments
Erin Onat

Are you for real? Understanding and Troubleshooting Artificial Transients in AFT Impulse

Around this time of year with Thanksgiving just around the corner, I always reflect on the truly endless list of things I am so grateful for. While this list is by no means exhaustive, some of these things include my loved ones, my awesome job at AFT, the bounty of pumpkin-flavored treats that sweeten up my fall-time snacking options, and of course, AFT Impulse’s detection of artificial transients. While the dreaded Warning message that an artificial transient triggers can cause any engineer’s stomach to turn, I’ll explain why every AFT Impulse user should add this feature to his/her list of...
Continue reading
Recent Comments
alen
Thank you Erin for drawing our attention to this issue. One thing that I miss here is HOW to resolve the issue. How to specificall... Read More
Tuesday, 14 November 2017 09:52
Erin Onat
Thank you for taking the time to read my blog and to give me some feedback! The model discussed in this blog involves a somewhat... Read More
Friday, 01 December 2017 01:40
  1633 Hits
  2 Comments
Trey Walters

The Knowledge Quest: Connecting With Fluids Education at Universities

This week was not a typical week for me. For the first time in 30 years I found myself in not one, not two, but three university classrooms. Each classroom was in one of Colorado's excellent engineering schools.

I had a chance to come face-to-face with about 140 students in classrooms this week and several professors. A number of positive things came of the week which I will summarize below.

Continue reading
  521 Hits
  0 Comments
Abby Zimmerman

Using Branch Junctions to Model Desuperheaters

Superheated steam is often used in mechanical power applications, such as driving turbines. For heating or industrial processes, however, saturated steam is more efficient. Desuperheaters are used to lower the temperature of superheated steam, so that it can be more effectively used in industrial processes. A desuperheater lowers the temperature of the steam by injecting water. Now, the question is, how can you model a desuperheater within AFT Arrow? AFT Arrow  is a single-phase program for compressible flow, so it cannot model liquid water. Conveniently though, there is a feature built into the branch junction that can model a desuperheater....
Continue reading
  929 Hits
  0 Comments
Trey Walters

Hydropower Big and Small: My Recent Visit to a 5 MW Plant

Pikes Peak in Colorado, USA is often called "America's Mountain" and is the most visited mountain in North America and second most visited in the world. Barr Trail is the 13 mile (20 km) hiking trail that leads from Manitou Springs to the top of Pikes Peak. And right next to the Barr Trail trailhead is the famous 100+ year-old Manitou Hydro Plant.

Famous? Why is this tiny 5.5 MW hydroelectric power plant famous?

And how would a fluid systems engineer like myself compare it to other famous dams like the 14,000 MW Itaipu Dam and the 2,000 MW Hoover Dam?

Continue reading
  846 Hits
  0 Comments
Trey Walters

Hurricanes and the Art of Computer Modeling

Hurricane Irma ravaged the Caribbean Islands and the state of Florida. Sixteen days prior, Hurricane Harvey ravaged the coastal area of Texas. Weather experts said this was the first time in recorded history that two Category 4 hurricanes made landfall in the United States in the same season. Each hurricane caused billions of dollars in damage and impacted millions of people.

Especially in Irma’s case, there was considerable discussion of the computer modeling used to predict the path and strength of the hurricane. As I have worked in computer modeling for most of my 30+ year career, this piqued my interest and I decided to educate myself a little more on the topic as it relates to hurricanes.

The first resource I pursued is one of our software developers here at AFT, John Lindsay. John has an undergraduate degree in Meteorology and a Master’s degree in Computer Science. John is a self-described weather geek who has a weather station at his home. We talked about weather modeling and he gave me some links to read further, which I did.

Continue reading
  1051 Hits
  0 Comments