Multi-Wavelength Densitometer for Experimental Research on the Optical Characteristics of Smoke Layers

Abstract A novel multi-wavelength densitometer was built for the purpose of continuous and simultaneous measurements light obscuration in smoke layers, concurrently five bands (λ = 450 nm, 520 658 830 nm 980 nm). This device used determining transmittance visibility parameters a layer from fire 1.00 dm 3 n-Heptane 0.33 × m tray located test chamber (9.60 9.80 4.00 ). The performance compared with commercial Lorenz at 880 nm. Significant differences measured value were observed between different sensors – 65% (blue light), 80% (red light) to 95% (IR). smoke, estimated following theory Jin reflecting signs (K 3), ranged 7.5 12 light-emitting 8) 18 32 m, respectively. performed experiment has confirmed applicability added light-extinction experiments. sensitive temperature variations requires active cooling careful warm-up prior experiments, reach expected sensitivity.