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针对矩形通道内伴随水蒸气冷凝的烟气对流换热,建立显热和潜热火积平衡方程,并导出火积耗散的表达式.利用火积耗散极值原理获得了伴随冷凝的烟气对流换热的场协同方程,并通过数值求解包括场协同方程在内的控制方程组,得到了矩形通道内的最优速度场为多纵向涡的流动结构,该流型提高了速度场与温度场、速度场与浓度场之间的协同程度,从而可以在黏性耗散增加较小的条件下使传热传质过程得到显著强化.在通道内布置不连续双斜肋可以产生接近于最优流场的多纵向涡流动,在Re=600时,与光滑通道相比,不连续双斜肋通道中烟气的总换热量增加29.02%,冷凝换热量增加了27.46%.
Aiming at the convection heat transfer of flue gas with water vapor condensation in a rectangular channel, an equilibrium equation of sensible heat and latent heat is established and the expression of dissipation of fuming product is deduced.The flue gas with condensation Convection heat field synergistic equation, and by numerical solution of the governing equations including the field synergetic equations, the optimal velocity field in the rectangular channel is the flow structure of the multi-longitudinal vortex, which increases the velocity field and temperature Field, velocity field and concentration field, so that the heat and mass transfer process can be significantly strengthened under the conditions of small increase of viscosity dissipation.Discontinuity of double oblique ribs in the channel can produce close to the maximum When Re = 600, the total heat exchange of flue gas in discontinuous double inclined channel increases by 29.02% and the heat of condensation increases by 27.46% compared with that of smooth passage.