结晶垢结垢过程的传热传质模型

通过对结晶垢结垢过程传热传质机理的分析,证明了垢层表面温度随时间的变化会对结垢过程产生重大影响.据此提出了考虑垢层表面温度变化的描述结垢过程的传热传质模型.对恒壁温和恒热流条件下的结垢过程进行了详尽的分析和讨论.结果表明,对恒壁温情况必须考虑垢层表面温度随时间的变化,这一变化是导致结垢过程渐近特性的重要原因之一;而对恒热流情况,垢层表面温度随时间的变化很小,可以忽略它所带来的对结垢过程的影响.与实验数据比较表明,模型预测是正确可靠的.

A HEAT MASS TRANSFER MODEL OF SCALING PROCESS

It is shown by the detailed analysis of its heat mass transfer mechanism that the variation of the surface temperature of scaling layer has an important influence on the scaling process. A heat mass transfer model is constructed to take the variation of the scaling layer surface temperature into consideration. With the model, simplified analyses of the scaling processes are carried out under both the constant wall temperature and the constant wall heat flux conditions. The results show that the variation of the scaling layer surface temperature is one of the major factors that cause the asymptotic tendency of scaling process. Comparisons of the model with experimental data are given. The results show that the present model can give a very good prediction of the experimental results.