Overview of AFT Impulse

Welcome to AFT Impulse™ - a visual platform for modeling fluid transients in pipe networks! See what's new in version 9!

AFT Impulse brings increased productivity to the pipe flow engineer by combining traditional analysis with an intuitive graphical user interface. By implementing a drag-and-drop method of pipe flow modeling, AFT Impulse simplifies the pipe network modeling process.

AFT Impulse can show both input data and analysis results in visual form, allowing rapid analysis of a model's validity. Identifying poor assumptions, catching typographical or modeling errors, and rerunning models are all accelerated because of AFT Impulse's graphical environment.

Whether your pipe system model will be used to evaluate and improve an existing system or to design a new one, AFT Impulse increases your productivity in the modeling process.

What Can AFT Impulse Do?

AFT Impulse can be used to model a wide variety of incompressible flow systems, including:

• Open and closed (recirculating) systems

• Network systems that branch or loop, with no limit on the number of loops

• Systems with valve transients

• Systems with pump transients

• Systems with pressure or flow control valve transients

• Systems with transient cavitation and liquid column separation

• Systems with surge suppression devices such as accumulators, surge tanks and air valves

• Systems with variable density and viscosity

• Multiple design cases in a single model file (Scenario Manager)

• Non-Newtonian fluid behavior

AFT Impulse's steady-state solution engine is based on standard techniques used for many years in industry. The Newton-Raphson method is used to solve the fundamental equations of pipe flow that govern mass and momentum balance. Solutions are obtained by iteration, and matrix methods optimized for speed are employed to obtain convergence. Once a steady-state solution is obtained, AFT Impulse simulates the transient using the Method of Characteristics, the most widely used method for solving fluid transient problems.

Where to Start

The best place to start learning about AFT Impulse is to work through our example problems and video tutorials found in the Impulse Learning Resources.

Add-on Module Capabilities

AFT Impulse has two add-on modules that extend modeling capabilities.

• Pulsation Frequency Analysis (PFA) allows the engineer to study the pressure pulsation effects a positive displacement pump has on a system.

• Predict resonant frequencies

• Graphically show the frequency response of a system

• Examine the pressure response of a system when a positive displacement pump is running at a resonant frequency

• Ensure the pressure pulsation magnitudes comply with the API-674 standard

• Settling Slurry (SSL) allows the engineer to perform waterhammer analysis while accounting for the complex property and system interactions associated with slurry flows.

• Model homogeneous and pseudo-homogeneous slurry mixtures

• Slurry pump performance de-rating

Who Can Use AFT Impulse

AFT Impulse assumes that the user possesses a good general knowledge of engineering pipe system hydraulics and has at least a basic understanding of the fluid transients and surge phenomenon. Even the most advanced and easy-to-use software package cannot make up for a lack of fundamental knowledge on the part of the user.