Experimental Studies of the Effect of Spray Dynamics on Radiation Blockage by Water Curtains
As a widely used protection device, the radiation blockage ability of water spray curtain to high temperature heat source is influenced by a number of elements, of which spray dynamics characteristic of nozzles is an important factor. An experimental study on radiation attenuation ability of water sprays has been carried out in laboratory. Droplets diameters and distributions of varied positions have been measured by laser particle sizer at different pressures. The position range varies from 25 to 175 cm and pressure changes from 1 to 3 bars. The attenuated radiation fluxes are measured by radiation heat flux meters to analyze the transmissivity of sprays. The results clearly indicate that the spray dynamic characteristic can severely affect the blockage ability of thermal radiation. The variation tendency of particle mean diameter can directly reflect the change trend of attenuation efficiency. Characteristic of droplets and relative positions of protected objects are two significant factors for affecting attenuation efficiency. These factors should be considered when water spray curtains are to be used in industrial and building fire protection. Furthermore, different nozzles with different characteristics, which should be measured firstly when they are used to discharge the water sprays.
KeywordsWater curtains Droplet size Particle distribution Spray dynamics Radiation blockage
This research was supported by the National Natural Science Foundation of China (No. 51706218), State’s Key Project of Research and Development Plan (2018YFC0808600) and the Natural Science Foundation of Navy (No. 435517D25).
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