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针对光管和四种不同结构的强化管(缩放管Ⅰ、缩放管Ⅱ、弧线管及波纹管)在相同条件(工质流速、入口温度、水浴温度及微粒浓度)下的颗粒污垢实验数据,基于普朗特类比法,以φ(φ=(K_m/K_(mp))/(f/f_p),K_m为质量传递系数,f为摩擦因子,下标p表示光管)和ψ(ψ=(j/j_p)/(f/f_p)~(1/3),j为传热因子)作为传热性能评价指标,η_φ(η_φ=(R_f/R_f_p)/φ,R_f为渐近污垢热阻)和η_ψ(η_ψ=(R_f/R_f_p)/ψ)作为换热面综合评价指标,结合强化管内流场模拟情况,进行分析。结果表明:不同类型的强化管,渐近污垢热阻比R_f/R_f_p与φ及ψ值的大小并非存在增函数关系;在给定的实验条件下,弧线管的综合性能优于其它三种强化管。所述方法为污垢研究工作提供有益参考。
Experimental data on particle fouling under the same conditions (working fluid flow rate, inlet temperature, water bath temperature and particle concentration) for a light pipe and four different types of reinforced pipes (tube Ⅰ, tube Ⅱ, arc tube and bellows) , Based on the Prandtl analogy method, the mass transfer coefficient is φ (φ = (Km / K mp) / (f / fp) and Km is the mass transfer coefficient, f is the friction factor, = (j / j_p) / (f / f_p) ~ (1/3), j is the heat transfer factor), η_φ (η_φ = (R_f / R_f_p) / φ, R_f is the asymptotic fouling heat Resistance) and η_ψ (η_ψ = (R_f / R_f_p) / ψ) as the comprehensive evaluation index of the heat transfer surface, and combined with the simulation of the flow field in the intensified pipe. The results show that the asymptotic fouling resistance ratio Rf / R_f_p and the value of φ and ψ do not exist an increasing function in different types of strengthened tubes. Under the given experimental conditions, the comprehensive performance of arc tubes is better than the other three Strengthen the tube. The method provides a useful reference for the research of fouling.