高爐冷卻壁肋骨設計對熱負荷的影響

本研究以計算流體力學(CFD)建立高爐冷卻壁受爐內熱氣沖刷的模擬技術，探討部分高爐操作參數以及冷卻壁的肋骨形狀、幾何尺寸對於熱負荷的敏感度分析，可提供國內煉鋼產業進行高爐冷卻壁時的設計參考，得到的成果如下: 以高爐的操作環境與參數來看，爐氣溫度提升對於冷卻水溫的影響不顯著，但是對於肋骨熱面溫度的影響較大；焦炭填充時應注重均勻性，因為填充床均勻性對於高爐熱負荷會產生極大影響。當加長水道封口段長度可以消除死水區和冷卻水的局部高溫；梯型肋骨和佛手型肋骨在更改冷卻壁尺寸所造成的效應相同，加大肋骨厚度會造成冷卻壁的熱阻增加，對於整體熱負荷有負面的影響，建議可設計在40~50mm即可；固定肋骨大小，改變肋骨比例對於總熱傳率的影響會受到互補的效應，所以整體熱負荷的變化不明顯，因此在設計時不需過度考慮此項參數；肋骨的最小寬度設計應在50mm以上為佳，因為寬肋骨可以加強肋骨的散熱能力。梯型肋骨冷卻壁因為形狀所造成的流場分佈和散熱性能都可以幫助降低熱傳率和肋骨溫度，這兩項指標上都優於佛手型肋骨冷卻壁。

關鍵字

計算流體力學；高爐；冷卻壁；填充床；熱負荷

並列摘要

A CFD-based finite volume model for cooling stave had been established to study the thermal load of Blast furnace cooling stave. The simulation technique is utilized to investigate the effects of blast furnace operating parameters, rib shape, and geometry of the stave on thermal load. This research can provide the design guides for developing blast furnace stave to steelmaking company. The conclusions are as follows: When the gas temperature inside furnace is increased, the temperature on rib hot surface is also increased but the cooling water temperature rarely affected. The coke filling in the furnace should be uniformity for its great effect on the blast furnace thermal load. Lengthening the length of the waterway seal can eliminate the dead zone of water path and lower the local maximum of cooling water temperature. The trapezoid-shaped stave and buddha-hand-shaped stave has the same effect in changing the size of the rib. Increasing the thickness of rib will enhance the thermal resistance of stave, which has a negative effect on thermal load, 40~50mm is a suitable rib thickness range; Fixing the size of rib, changing the proportion of rib will have a complementary effect on the total heat transfer, so the change in thermal load is not obvious. Hence, it is not necessary to emphasize this geometry parameter during design; The minimum width of rib should be designed to be more than 50mm, because the wider rib can enhance the heat dissipation performance of rib; Because of the difference in rib shape, the flow field distribution and heat dissipation performance of the trapezoid rib stave can help reduce heat transfer and rib temperature, both of two thermal load targets are superior to Buddha-hand-shaped rib.