水面蒸发计算模型研究

根据水面蒸发形成机制和水面蒸发量与气象要素关系的试验分析结果 ,选择饱和水汽压差、风速、相对湿度作为水面蒸发计算因子 ;综合国内外水面蒸发计算研究成果 ,选取适用的风速函数和相对湿度函数 ,提出一种具有较强适应性的水面蒸发计算模型 .简要评析目前国内出现的 3个水面蒸发全国通用计算公式 ,指出这 3个公式尚存在欠缺 ,有待进一步完善 ;最后提出水面蒸发计算模型研究应统一水面蒸发量标准 ,正确选择风速函数 ,并应加强水面蒸发计算模型空间变化规律的研究 .

Calculation model for water surface evaporation

Based on the mechanism of water surface evaporation and the relationships between the amount of evaporation and key meteorological factors, the saturated vapor pressure difference, wind speed, and relative humidity were taken as calculation factors. By analysis of evaporation calculation at home and abroad, applicable functions of wind speed and relative humidity were selected, and a calculation model of high practicability was developed for evaporation calculation. Besides, three calculation formulas commonly used in China were analyzed, and it is concluded that the formulas need to be further improved because of some disadvantages in them. Finally, it is pointed out that unification of the evaporation standard, reasonable selection of a wind speed function, and the finding of the regularity of spatial variation of evaporation are necessary for research of the evaporation calculation model.