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建立了碳酸钙于换热表面结垢的传热传质模型.模型中不仅考虑了换热表面的析晶污垢,同时也考虑了由于过饱和在溶液中成核而形成的颗粒垢.对混合污垢的沉积与脱除分别予以表达,并将结垢过程的溶液及污垢特性应用其中.另外,模型还根据换热器中垢层传热的特点综合考虑了结垢与温度场的耦合作用,得到了换热表面污垢热阻随时间变化的数值.模型预测与实验数据吻合得很好,偏差大部分小于15%,说明预测模型是正确可靠的.
The heat and mass transfer model of calcium carbonate on the heat transfer surface was established.The model not only considers the crystallization fouling on the heat exchange surface but also considers the particle scale formed by the supersaturation nucleation in solution. The deposition and removal of fouling are respectively expressed, and the solution and fouling characteristics of the fouling process are applied to them.In addition, the model also takes into consideration the coupling between fouling and the temperature field according to the heat transfer characteristics of the fouling layer in the heat exchanger, The thermal resistance of fouling on the heat transfer surface is obtained with the change of time.The model predictions are in good agreement with the experimental data and most of them are less than 15%, which shows that the prediction model is correct and reliable.