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实验研究发现射流冲击条件下铜、镀镍铜及铝表面有碳酸钙结垢状况。考查不同水质硬度、不同金属表面下换热表面的结垢过程,获得渐进型的污垢热阻随时间的变化曲线。实验结果表明:随着水质硬度的增加,铜片、镀镍铜片及铝片表面的结垢速率都加快,诱导期减小,铜片与镀镍铜片或者铜片与铝片之间的污垢热阻渐进值的差值越来越大。当水质硬度为500、700 mg/L时,相对铜片、镀镍铜片而言,铝片的诱导期最长,污垢热阻渐进值最小,但是,当水质硬度为300 mg/L时铝片的污垢热阻渐进值却最大。
Experimental study found that jet impact conditions copper, nickel-plated copper and aluminum surface calcium carbonate scaling conditions. To examine the scaling process of different water hardness and heat transfer surfaces under different metal surfaces, a gradual curve of fouling thermal resistance with time was obtained. The experimental results show that with the increase of water hardness, the scaling rate of copper, nickel-plated copper and aluminum surface are accelerated, the induction period is reduced, copper and nickel-plated copper or between copper and aluminum The fading resistance of fouling gradually increases. When water hardness is 500,700 mg / L, the induction period of aluminum is the longest, and the fading resistance of soil is the smallest compared with copper and nickel plated copper. However, when the water hardness is 300 mg / L, aluminum Film fouling resistance is the largest gradually.