AFT Blog

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. One of the most powerful aspects of AFT’s implementation of heat transfer is that energy is balanced across the entire system. For example, you can observe changes in pump or control valve operation when adding heat transfer to a remote part of a system. Looking at...

There are many (six!) ways to define a pump transient event in AFT Impulse. This gives you great flexibility in creating a model that behaves the way you want it to. One thing true for all pumps is that they must be started at least once. Pump startups often cause significant transient effects on the system so you may wish to model this with AFT Impulse. Even narrowing your pump transient down to a startup, there are still four models left to choose from: Without InertiaStartup With Inertia and No Back Flow or Reverse SpeedStartup With Inertia - Four Quadrant, Known...

To define any transient event in AFT Impulse or AFT Fathom XTS the application must know when it begins. To do so, the user should know how time and event logic is approached in AFT’s transient solvers. In this article, we will discuss the three different time bases used in the applications, the selection of a single or repeating event, and the many possible triggering events that can start the user defined transient. The user defines these items in the Initiation of Transient section of the junction’s Transient tab. The requirements for each junction can vary, but the general approach applies...