Spectrally Adapted Red Flares With Enhanced Color Quality and Luminous Intensity

Abstract

The production of bright light, with vivid color, is the primary purpose of signaling, tracing, illuminating devices, highway distress flares, and aerial fireworks. This study, reports on the development of red flame compositions with enhanced performance in terms of luminous intensity, color quality, and action time to standard red flare R-284 NATO. A systematic study was conducted in an attempt to optimize different factors that could affect the red flare performance. The explored parameters are the binder type and fuel, as well as the proper assortment between fuel/oxidizer and color emitter/color intensifier. The light intensity as well as the imprint spectra of developed red flares to reference (R-284 NATO) was measured using digital luxmeter DL 1076 by Miltronics and UV-Vis. spectrometer USB 4000 by Ocean optics. The main giving of this study is that the light intensity of R-284 NATO was increased by 72 % , the color quality was also improved by 60 % by means of optimizing the ratio of color intensifier poly vinyl chloride (PVC) to color source Sr(NO 3 ) 2 using novel metal fuel (Al). This is the first time ever; aluminum fuel has been employed in red flare formulations. Aluminum-based formulations were found to maximize the formation of red color reactive emitting species (SrCl), and to minimize the interfering incandescent emission resulted from MgO and SrO. The combustion gaseous products particularly the Wt.% of active red color emitting species was evaluated using chemical equilibrium thermodynamic code named ICT (Institute of Chemical Technology in Germany, Virgin 2008) to judge the quality of the developed red light. The improvement in red flare performance was achieved by implementing the general rule that the color intensifier should be in the range from 10-15 Wt.% of the total composition. Applied loading pressure (for sample preparation) higher than 50 bars was found to decrease the light intensity. This study might open the route for the development of tailored and effective colored flame compositions as well as infra-red flares.