【摘要】 应用提出的新三维数学模型于90tRH装置内RH和RH-KTB精炼中钢液的脱碳,结果表明,本工作条件下,整个精炼中由气泡穿过液相时所作曳力功、流动和扩散及化学反应等非平衡过程引起的体系内耗散函数κ2的值不大,体系整个流场内非线性耗散因子qe(κ)≈1;体系内熵产生和能量耗散随精炼的进行很快减小;与气泡穿过液相时所作曳力功、粘性和紊流耗散及扩散相比,C-O反应对体系内熵产生和能量耗散起主导作用,低碳和超低碳钢的RH精炼似乎接近非平衡态的线性区;粘性和紊流耗散及扩散对非平衡活度系数的影响可忽略,除发生化学反应的部位(上升管区段和真空室熔池)外,RH装置中其他部位钢液内碳和氧非平衡活度系数的非平衡分量都趋于1;非平衡效应(主要是碳氧反应)对RH精炼中钢液的脱碳有抑制作用.与不考虑非平衡效应的情况相比,该模型能更合理和精确地模拟RH精炼中钢液的脱碳.更多还原

【Abstract】 The results obtained by applying the novel three-dimensional mathematical model proposed and developed earlier paper [1] to treat the decarburization of molten steel during the RH and RH-KTB refining in a 90 t RH degasser presented that under the conditions of the present work, the values of Rayleigh-Onsager dissipation function κ2 in the system, caused from the work done by the drag force as the bubbles passing through the liquid phase, viscous and turbulent flow, mass diffusion and chemical reaction and other non-equilibrium processes, were not large during the throughout refining, and ≤ 1.0×10-13, thus the non-linear dissipation factor qe(κ)≈1 was held everywhere in the whole flow field of the system. The entropy production and energy dissipation in the system rapidly decreased with increasing of the refining time. The C-O reaction itself played a more leading role in the entropy generation and energy dissipation in the system, and the RH refining of low and ultra-low carbon steel seemed to be close to the linear zone of the non-equilibrium state. The influence of the viscous and turbulent flow dissipation as well as diffusion processes on the non-equilibrium activity coefficients of C and O in the liquid steel could be ignored. Except in the regions (the up-snorkel zone and the bath in the vacuum vessel) where the C-O reaction took place, the non-equilibrium components of non-equilibrium activity coefficients of C and O in the steel at the other places in the degasser were all approaching to one. The non-equilibrium effects (principally, the C-O reaction itself) had a restraining on the decarburization of liquid steel in the RH refining. This model would be able to simulate more reasonably and precisely the decarburization during the RH refining of molten steel than that without considering the effects.更多还原