为研究不同浓度的有机混合工质对预冷段流场特性的影响规律,以不同浓度的乙醇、乙二醇作为冷却介质在不同液气比条件下的工况中进行数值模拟。结果表明:无论是蒸发率还是蒸发量,都会随着有机工质浓度的增加而有所提高,其中乙醇溶液更佳,增幅跨度约20%,且浓度的变化规律与液气比互不影响；受限于换热能力的强弱,当有机物浓度越低时,流场的温降效果更好,差值大小也取决于液气比,在液气比为3.3%条件下,不同浓度的乙醇溶液温降差值为3.15K,乙二醇溶液为3.46K；流场的压降损失受多个因素的共同影响,并非呈单一的线性关系,伴随着液气比的增加,高浓度的有机工质可以减少压力损失,但在进气速度略低的条件下则相反；对于流场出口均匀度,与溶液浓度基本是正相关,且易蒸发的工质如乙醇对均匀度的影响更大。

In order to study the effect of different concentrations of organic mixed working medium on the flow field characteristics of the pre-cooling section, the numerical simulation was carried out with different concentrations of ethanol and ethylene glycol as the cooling medium under different liquid-gas ratio conditions. The results show that both the evaporation rate and evaporation amount increase with the increase of the concentration of organic working medium, and the increase span of ethanol solution is about 20%, and the change of concentration has no influence on the liquid-gas ratio. Limited by the strength of heat transfer capacity, when the concentration of organic matter is lower, the temperature drop effect of the flow field is better, and the difference depends on the liquid-gas ratio. When the liquid-gas ratio is 3.3%, the temperature drop difference of ethanol solution and glycol solution with different concentrations is 3.15K and 3.46K. The pressure drop loss of flow field is affected by many factors, and it is not a single linear relationship. With the increase of liquid-gas ratio, high concentration of organic working medium can reduce the pressure loss, but it is opposite under the condition of slightly lower intake speed. The outlet uniformity of the flow field is positively correlated with the concentration of the solution, and the evaporative working medium such as ethanol has a greater influence on the uniformity.

V235.1

哈尔滨工程大学高水平科研引导专项（3072022QBZ0302）