Optimal Orientation of a Liquid-Film Solar-Assisted Brine Concentrator

Recently, an open, liquid-film concentrator has been both theoretically and experimentally evaluated for increasing evaporation and concentration rates above those for simple solar evaporator basins (Kim, D. H., Jenkins, B. M., Yore, M. W., and Kim, N. J., 2007, “Salt Recovery From Agriculture Drainage Water Using a Liquid Film Solar-Assisted Concentrator: Simulation and Model Validation,” Sol. Energy, 81(10), pp. 1314–1321). For azimuth and tilt angles of the inclined brine concentrator where the maximum solar gain and mean wind direction are not in concurrence, the optimum orientation to maximize evaporation over a fixed interval of time was determined by simulation. Simulation was performed using ten years of hourly weather data for two different locations where wind blows mostly from the south and the north throughout the year, respectively (Davis and Five Points, CA) with different orientations and slope angles. Maximum annual evaporation for Davis occurred with the concentrator facing southwest and sloped at the latitude angle. At Five Points, maximum evaporation occurred with the inclined surface facing north even with the less favorable angle for solar absorption, indicating the importance of the wind speed-dependent mass transfer coefficient on overall performance. Additional experiments are needed to validate the simulations.