A Three-Flux Method for Predicting Radiative Transfer in Aqueous Suspensions

A three-flux method is formulated for predicting radiative transfer in aqueous suspensions. The radiation field is resolved into three components, and the physical effects which are considered include refraction at the air-water interface, highly anisotropic scattering in the suspension, and diffuse reflection at the bottom. Calculations are performed for wide ranges of the scattering albedo, bottom reflectance, optical depth and irradiation, and results obtained for the local radiation flux and volumetric absorption, as well as for the overall suspension absorptance and the reflectance of the suspension-bottom complex, are in good agreement with those obtained from the more detailed method of discrete ordinates. Excellent agreement is also obtained between predictions of the net radiative flux in the suspension and measurements obtained for a suspension of unicellular algae.