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实验研究了内插螺旋线圈的水平圆管内30~#透平油的对流强化传热及流阻特性,探索了螺旋丝径的影响。实验圆管为φ10×0.5×900mm的紫铜圆管。其它参数范围为:193.97≤Pr≤464.36;2.7×10~2≤Re≤2.5×10~3;0.333≤t/D≤1.333和3.75≤t/d≤24.实验表明,Re及丝径的增大均使换热系数及阻力增大;Re的增大亦同时造成h/h_及△P/△P_两个比值的增加。Pr的减小可使换热增强,流阻减小,采用(Nu/Nu_)/(f/f_)~(0.29)作为评估传热及流阻综合性能的判据,实验范围内该判据之值介于2.09～3.23之间。此外,综合实验数据得到了传热及流阻两个关系式。
Experiments were carried out to study the convective heat transfer and flow resistance characteristics of 30 ~ # turbine oil in a horizontal circular tube with interpolated helical coils. The effects of the helical fiber diameter were explored. Experimental tube is φ10 × 0.5 × 900mm copper tube. Other parameters range: 193.97≤Pr≤464.36; 2.7 x 10 ~ 2≤Re≤2.5 x 10 ~ 3; 0.333≤t / D≤1.333 and 3.75≤t / d≤24. Experiments show that the increase of Re and wire diameter The larger the heat transfer coefficient and resistance increase; Re also increases the h / h_ and △ P / △ P_ two ratio increases. The decrease of Pr can enhance the heat transfer and decrease the flow resistance. The criterion of heat transfer and flow resistance performance is adopted as (Nu / Nu_) / (f / f_) ~ (0.29) The value is between 2.09 ~ 3.23. In addition, the experimental data obtained two relations of heat transfer and flow resistance.