Water mist suppression

The largest volume of hydrauHc fluids are mineral oils containing additives to meet specific requirements. These fluids comprise over 80% of the world demand (ca 3.6 x 10 L (944 x 10 gal))- In contrast world demand for fire-resistant fluids is only about 5% of the total industrial fluid market. Fire-resistant fluids are classified as high water-base fluids, water-in-oil emulsions, glycols, and phosphate esters. Polyolesters having shear-stable mist suppressant also meet some fire-resistant tests. 

Water mist systems are intended for rapid suppression of fires using water discharged into completely enclosed limited volume spaces. Water mist systems are desirable for spaces where the amount of water that can be stored or that can be discharged is limited. In addition, their application and effectiveness for flammable liquid storage facilities and electrical equipment spaces continues to be investigated with optimistic results. Water mist systems are also used for gas turbine enclosure protection. 

A. Dvorjetski, J.B. Greenberg Effects of water-mist dynamics and droplet size in suppression of counterflow diffusion flames. Seventh Asian-Pacific Conference on Combustion (ASPACC 09), Tapei, May 2009. 

Keywords Fire suppression Flame extinguishment Flame suppression screens Flash vaporized sprays Spray transport Sprinklers Water mists... 

Water-mist systems (with droplet sizes less than 100 pm) have been considered as replacements for Halon 1301. Phase Doppler interferometry has been used to characterize various surrogate fluids in misted liquid sprays that are generated by different screens [7, 28, 29]. The effect of mist droplet diameter (< 200 pm), density, and injection angle have shown that when the mist and flame are aligned spatially, flame suppression is enhanced with increased density, decreased velocity, and smaller size droplets [30]. Larger droplets and injection angles become important for asymmetric mist/flame alignment. Efforts to decouple the physical (suppression due to droplet size and dynamics), thermal (due to heat capacity and... 

J. R. Mawhinney Water mist fire suppression systems. In Cote, A.E., (ed.-in-chiel) Fire Protection Handbook (20th ed.). Volume n. Section 16, Chapter 8, NFPA, Quincy (2008). 

K. Prasad, C. Li, K. Kailasanath Optimizing water-mist injection characteristics for suppression of coflow diffusion flames, 27th Symposium (Intemational) on Combustion, pp. 2847-2855, Combustion Institute, Pittsburgh (1998). 

Michigan, Ann Arbor, MI 48109-2125, USA. Email MtnK aig)imiirli odn. Ph (734) 647-4790, Fax 647-3170. Water mist is also used for fire siqipression as a substitute fiv hakm suppression agents. The challengBS here ate also to increase the cooling rate as mudi as possible wife die consliaint of not wetting the electronic surfiices. 

Kalhan, S.N. Mann,J. T Denis,R.A. Sulfonate C ontaining Copolymers as Mist Suppressants in Water-Based Metalworking Fluids. European Publication Reference 08116772A2, (1997)... 

Wet dust suppression systems include external water sprays, water injection through the drill, and foam injection though the diiU. External boom-mounted systems are t5q)icaUy homemade and reduce dust by about 50%. Water-mist injection through the drill is available from several manufacturers. The resulting dust reduction is much better, typically 90% or more. A homemade foam system has also been used successfully (USBM 1982c). It achieved 95% dust reduction at lower water flow rates. 

Control Spray fruit trees with dormant oil to kill overwintering eggs in garden or greenhouse rinse plants with water and mist daily to suppress reproduction of mites release predatory mites Metaseiulus occiden-talis on fruit trees, Phytoseiulus persimilis or similar species on vegetables, strawberries, and flowers spray insecticidal soap, pyrethrin, or neem as a last resort, spray infested plants with avermectins. 

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