INFLUENCE OF A SPATIAL DISTRIBUTION INHOMOGENEITY OF DROPLETS ON THE WATER CURTAIN SHIELDING PROPERTIES
DOI:
https://doi.org/10.20535/2305-9001.2014.72.37206Keywords:
water curtain, thermal radiation shielding, transmittance, thickness of water equivalent layerAbstract
Purpose. Development of calculated techniques for thermal radiation shielding by a water curtain and performing numerical calculations of its transmittance for fire thermal radiation.
Methodology. The central objective of the study is to develop calculation method of some major parameters of this mathematical model. These are such parameters: velocities of droplets moving, their concentration in space, thickness of equivalent layer of water, transmittance. Earlier there was no such calculation procedure, and determination of these parameters was made by means of the difficult experimental measurements. In this study the submerged jet theory is applied for calculation of these parameters. Subject of the theoretical analysis is the flat fan sprays which flow from the system of slot-hole sprinkler. The formulae received in the work allow to carry out calculation of called parameters on the basis of design characteristics of drencher installation. The graphic dependences constructed on the formulae allowed to define spatial distributions of these parameters.
Findings. Calculated formulae for the axial velocity of the sprayed stream, for volume ratio of water, for thickness of equivalent layer of water, for a thermal radiation transmittance, which take into account the inhomogeneity of a spatial distribution of droplets.
Application of results. Determination of optimum parameters of water spray curtain for the thermal radiation attenuation during fire suppressionReferences
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