Processes of Radiation Heat and Evaporation of Droplets and Their Influence on the Shielding Properties of Fire Water Curtains
Keywords:Fire water curtain, Thermal radiation shielding, Evaporation of droplets
Background. Water curtains are one of effective means of protection against fire thermal radiation. The analysis of the water curtain shielding properties is carried out by means of mathematical model operation. But the process of droplets evaporation as a result of their heating by fire thermal radiation is not considered in the existing mathematical model.
Objective. A central objective of the study is the analysis of processes of droplets radiant heating and evaporation, and also their influence on the water curtain shielding properties.
Methods. Thermodynamic analysis of the specified processes is made on the basis of the corresponding heat balance equations both for water curtain in general, and for separate droplets.
Results. Main results of the study are the numerical calculations and the graphic dependences of the parameters characterizing droplets evaporation for the typical regimes of thermal shielding. For the purpose of verification of the received results their comparison with results of earlier executed experimental studies on evaporation of water droplets at impact of laser radiation of infrared range was executed. It is established that theoretical results in limits of errors are in consent with the experimental results.Conclusions. The conclusion follows from the received results that evaporation of droplets owing to their heating by a fire thermal radiation has no essential impact on the shielding properties of water curtains. This process can be not considered when performing technical calculations.
A. Zharov et al., “Drencher curtains: theory and practice”, BDI, no. 5 (68), pp. 24–28, 2006 (in Russian).
D.I. Sobeshhans'kyj et al., “Water curtains in the systems of ensuring fire protection of various designation objects”, Naukovyj Visnyk UkrNDIPB, no. 2 (22), pp. 148–153, 2010 (in Ukrainian).
L.M. Meshman et al., Projection of Water and Foamy Automatic Installations of a Firefighting, N.P. Kopylov, Ed. Moscow, Russia: VNIIPO, 2002, 413 p. (in Russian).
А.N. Borodkin et al., “Problems of numerical modeling of water spray curtains produced by sprinklers: the publication review”, Pozharnaja Bezopasnost', no. 4, pp. 92–105, 2009 (in Russian).
W. Yang et al., “The interaction of thermal radiation and water mist in fire suppression”, Fire Safety J., vol. 39, pp. 41–66, 2004.
J.-M. Buchlin, “Thermal shielding by water spray curtain”, J. of Loss Prevention in the Process Industries, vol. 18, no. 4-6, pp. 423–432, 2005.
A. Collin et al., “Water mist and radiation interactions: application to a water curtain used as a radiative shield”, Numerical Heat Transfer, Part A: Applications, vol. 57, pp. 537–553, 2010.
A. Benbrik et al., “Contribution to fire protection of the LNG storage tank using water curtain”, Int. J. Thermal & Environmental Eng., vol. 2, no. 2, pp. 91–98, 2011.
A.G. Vinogradov, “Absorption of the radiant heat flux in the sprayed water jet”, Visnyk NTUU KPI. Ser. Mashynobuduvannya, no. 65, pp. 145–152, 2012 (in Russian).
A.G. Vinogradov, “Calculation method of water curtain parameters on basis of the submerged jet theory”, Naukovyj Visnyk UkrNDIPB, no. 2 (28), pp. 127–139, 2013 (in Ukrainian).
A.G. Vinogradov “Calculation method of water curtain shielding properties”, Pozharovzryvobezopasnost', vol. 23, no. 1, pp. 45–56, 2014 (in Russian).
A.G. Vinogradov et al., “Interrelation of fire water curtains parameters with their heat radiation shielding effectiveness”, Naukovyj Visnyk UkrNDIPB, no. 1 (31), pp. 36–45, 2015 (in Russian).
V.K. Rudash et al., “Evaporation of large water droplets under the influence of infrared radiation”, Kvantovaja Jelektronika, no. 5, pp. 21–26, 1973 (in Russian).
LicenseCopyright (c) 2017 NTUU KPI Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under CC BY 4.0 that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work