Abstract:
Evaporation characteristics of inclined falling film were studied under various working conditions by adopting electric heat instead of solar energy, while the still's distillate production rate predicted using Dunkle model based on temperature distribution of the liquid film and condensing surface by dividing both the heat-absorbing and the condensing surface into evenly-spaced segments. Results show that the heat flux density, feed water flow, inclination angle, and cooling water flow are the main factors affecting the distillate production rate, which increases linearly with the rise of heat flux density; when the feed water flow is within 5.5-10.0 kg/(h·m), the distillate production rate increases linearly with the decrease of feed water flow, whereas when the feed water flow is within 0.7-5.5 kg/(h·m), the distillate production rate basically remains unchanged; In the range of inclination angle varying from 15° to 60°, the distillate production rate increases as the inclination angle increases; The still's distillate production rate would be improved when the cooling water uniformly flows through upper half of the condensing surface. The more segments the heat-absorbing and the condensing surface are divided into, the better agreement would be between the predicted values and experimental results.