Firewater Flow Testing and Hydraulic Modeling for Large Industrial Facilities

A hydraulic model can be used to simulate flow scenarios for firewater systems in large petrochemical facilities. The primary purpose for constructing and calibrating a hydraulic model for a firewater distribution system is to create a tool that will provide a realistic representation of the system. A hydraulic model typically applies the Hazen-Williams (or Darcy-Weisbach) equation to calculate flows and associated pressure losses in pipes. Although the hydraulic model is a versatile tool, the C-factors of the model need to be “calibrated” to produce meaningful results. There are two traditional approaches for approximating the piping C-factors. One is based on the ages of the pipe, pipe sample, water quality, or other available historical data; another is based on observations from flow testing through an isolated flow path. However, these traditional approaches are generally not practical for large industrial facilities. An alternative Open‑Flow method, which does not require isolated flow path for flow testing, was developed to resolve the issues associated with the traditional flow testing methods. With appropriate planning, a firewater system can be flow tested in compliance with the code requirements, while the performance and internal piping condition of the firewater system can also be adequately evaluated.