Flow modeling for piping systems that no longer match their design

Steady-state hydraulic models of pump and piping networks, calibrated against your field measurements and used to test changes before anything is built.

Discuss your system
Stacked engineering drawings on a desk

When a model earns its keep

Piping networks drift from their design. Tie-ins get added, exchangers foul, valves get throttled to fix one problem and create another. A calibrated model shows where the flow is actually going and why.

  • Some users are short of flow while others are over-supplied
  • Pressure at the far end of the network has dropped since the last tie-in
  • Pumps are running at a different point than the design said they would
  • An expansion, reroute or new load has to be checked before the work starts

What the work covers

Each study ends with a working model and a written report covering the method, assumptions, results and recommendations.

  • Model development

    Built from P&IDs, isometrics, pump curves and equipment data sheets, in AFT Fathom for liquid systems.

  • Calibration

    Results compared with measured pressure, flow and temperature, and adjusted until model and plant agree.

  • Operating scenarios

    Normal, peak, standby and upset cases run on the same model to show flow distribution and pressure loss in each.

  • Modifications

    Proposed pipe, pump and valve changes tested on the calibrated model before money is spent in the field.

Pipework fitted with meters and valves
Power station cooling towers beside transmission lines

Nuclear station cooling-water model

The plant's cooling-water system runs as two trains for safety and redundancy. One train was modeled in full, the second train, built by another engineer, was independently checked end to end, and the model was calibrated to measured results for the system's major hydraulic loads.

Work performed by our team members before FSPG, shown as project experience.

See more project experience

Have a network that needs modeling?

Describe the system and the symptom. Drawings and any field readings can come later, once the scope is clear.

Further reading: A System Approach with Flow Analysis, Chemical Engineering, October 2021

Discuss your system

Flow modeling questions

P&IDs or isometric drawings, pipe sizes and materials, pump curves, and data sheets for heat exchangers, control valves and other equipment, plus any operating readings you have. Gaps can often be estimated and then checked during calibration.

An uncalibrated model shows how the system was designed to behave. Calibrating it against measured pressures and flows shows how it behaves now, with fouling, wear and every change made since construction, so the scenarios you run on it reflect the real plant.

Liquid networks are modeled in AFT Fathom and gas systems in AFT Arrow. Transient studies use AFT Impulse for liquids and AFT xStream for gas.

Yes. An existing AFT model can be reviewed, brought up to current conditions and recalibrated rather than rebuilt from scratch.

A question not covered here? Send it with a short description of the system.

Discuss your system