Water mist nozzles and systems are the ultimate development of fire-extinguishing technology. Initially developed for the marine industry, to be used in fire protection systems of crew and passenger cabins on board ferries, boats and cruise ships, later on these systems proved to be highly effective and suitable in many other non-marine applications.
In addition, their small size and the limited amount of water they need to function has allowed them to be used in new industrial sectors.
The water mist technology is relatively simple and it is based on the physical principle that a combustion process cannot sustain a fire if the percentage of oxygen present in the air is less than 11%.
According to this principle of thermodynamics, in order to extinguish a fire in a confined space or closed rooms with little ventilation, it is sufficient to evaporate a limited quantity of water in the air and introduce enough steam to reduce the ambient oxygen concentration below 11% and suffocate the flame.
It is evident that water fog fire protection systems cannot be used in external environments. In addition to producing standard water mist nozzles and a variety of special models upon customer’s request, as technology evolves, we continue to invest in research projects and feasibility studies to develop new spray nozzles, even more effective and practical.
A project we are currently working on, concerns a diffuser on whose hemispherical surface very small orifices can be distributed in any configuration, so that they spray jets can be adjusted and directed in any desired direction.
Precisely to be able to direct the spray jet in any direction, we developed a new water mist nozzle starting from a well-known principle based on the fluid dynamics of a straight jet at high speed in which the liquid is fractionated by the entrainment of air and the resistance to motion.
It was possible to produce such a straight stream by using very small diameter orifices in which the liquid is split at a short distance from the nozzle.
Reference: http://www.sdmantincendio.com/ing/water-mist-systems