基于CFD的两种紫外消毒模型的比较研究

为了预测紫外反应器的消毒效率,提高模拟的准确度,对两种紫外光强模型进行了比较分析。利用CFD技术,采用数值模拟的方法,对线源和柱源两种光强模型进行了光强分布以及消毒效率的模拟,并采用生物实验进行了验证。结果表明:与柱源模型相比,线源模型在近灯管处强度高42.3%,在1.2 cm处二者趋于一致;针对同一管式紫外反应器,透光率为95%时,线源模型的模拟结果偏大,柱源结果偏小;透光率为80%时,线源及柱源模型的模拟结果都偏大,流量及模型影响较小,透光率成为主要影响因素。综合比较,柱源模型适用于小型管式紫外灯消毒数值模型的开发。

Comparison of two different UV disinfection models by CFD

To predict the efficiency of UV disinfection reactor and improve the accuracy of numerical simulation,two different UV intensity models were compared.Intensity fields and disinfection efficiencies were simulated using line model and cylinder model.The results showed that compared with the cylinder model,line model gave 42.3% higher UV intensity near the UV lamp.Two models had similar results beyond 1.2 cm away from the lamp.Compared to the reduction equivalent dose(RED) from bioassay,the line model had higher RED values while the cylinder model had lower ones at 95% transmission rate,and both models had higher RED values at 80% transmission rate.Transmission rate was the main factor of RED in low transmission rate.Cylinder model is suitable for developing numerical simulation of the UV disinfection in annular reactors.