Double-sided wet fabric evaporator utilizing wind and solar energy efficiently — One-dimensional transient simulations

摘要

The performance of the double-sided fabric seawater evaporator suggested by Nosoko et al. (Desalination and Water Treatments (2010) 254) was simulated for a sunny day under subtropical and maritime climate conditions by a one-dimensional transient modeling. The concentration of seawater increases exponentially with the downstream distance along the fabric while the temperature and the evaporation rate increase gradually. In a polyester fabric, seawater flows fast and the concentration of the effluent brine is kept constant in a small range by adjusting the rate of influent seawater according with the solar radiation. In a cotton fabric, seawater flows slow, causes a large time lag between the influent and effluent, and thus varies the effluent concentration greatly. The temperature and evaporation rate of the polyester are approximately the same as those of the cotton. The daily evaporation is 9.41 kg/day m~2 -fabric under a solar radiation of 27.6MJ/m~2. Lumped capacitance model (Desalination and Water Treatment16 (2010) 254) was found to predict quite accurately the averages of the evaporation rate and temperature of fabric, but to fail in prediction of the temporal variations of the effluent concentration.