电站立式给水加热器传热强化及无铜化运行研究

针对电站立式给水加热器的传热特性和强度要求，研制并加工出小螺旋角内外螺旋翅片管（IOSF管）来强化其传热特性，基础试验表明，IOSF管的总传热系数比光滑管提高63%-95%；工业试验表明，采用IOSF管的立式高压加热器总换热系数提高43%，对钢螺旋槽管替代铜光滑管进行了实验研究，结果表明，钢质螺旋槽管给水加热器不仅能保证原有热负荷，还能提高其换热强度，实现了锅炉给水无钢化运行的要求。

Investigation on heat transfer enhancement for the erect water- feed preheater and non-copper running in power station

According to the demand of heat transfer and strength for the erect preheater in power station, a new type of heat transfer enhancement tube, namely the inside and outside triangles finned tube with small spiral angles (IOSF tube), has been developed and manufactured to improve its performance of heat transfer. The field experiment results show that the general heat transfer coefficient of the vertical IOSF tube is 63%~95%, lager than that of the smooth tube. The industrial experiment results show that for a erect high-pressure preheater with IOSF tube, its overall heat transfer coefficient enhances by 43% than the previous. Instead of copper smooth tube, some field and industrial experiments with steel spiral groove tube have also been carried out. The results show that the preheater with steel spiral groove tube not only guarantees the heat load, but also can improve its performance of heat transfer to meet the demand of no copper in water entering into boiler.