A wireless sensor network was used to measure water-flow rate in a fire hose. An accelerometer was chosen as the sensor to measure the flow rate based on the vibrations generated by water flowing through a fire hose close to the hose nozzle. These sensors are small, lightweight, and can attach to the outside of the hose, not obstructing the water’s flow path. A relationship between the dominant-frequency metric and the flow rate was applied and a custom graphical user interface for quick visual referencing developed to determine real-time water flow in a fire hose for improving fireground situational awareness.
The invention is a real-time wireless flow meter for a fire hose to improve situational awareness on the fireground. Currently water pressure measured at a fire engine is used to determine if water is flowing through a fire hose, but water pressure does not necessarily mean that water is flowing. NIST has developed a real-time wireless flow meter prototype to directly measure water flow rate in a fire hose. Additional research is needed to improve the signal metric and the physical robustness of the meter. Understanding the fire hose flow is critical for improving situational awareness for an incident commander and can reduce civilian and firefighter injuries and fatalities on the fireground.
The new aspect is that the flow meter uses accelerometers to detect vibrations within the fire hose and approximates the flow rate. Wired sensors, including accelerometers, have been attached securely to the outside surface of rigid pipes to measure fluid or gas induced pipe vibrations to determine flow rate within the pipe in research settings as well as in the utility pipeline industry. However, we applied the accelerometer to a flexible hose for the purpose of applying a wireless sensor network to fire hoses for a fire fighting application. To our knowledge, no existing product currently measures the flow rate of water at the nozzle end on the outside of a fire hose that is intended for use on the fireground.