在軋延製程前，鋼胚必須再進行加熱，使其溫度上升至約1500 K左右，以便達到塑性變形之程度，而在加熱過程中，鋼胚溫度分佈將影響鋼材機械性質與表面品質，且鋼胚整體溫度分佈若不均勻會影響到軋延製程的順暢性及厚度均勻狀況，故國內鋼鐵廠中加熱爐之溫控技術為鋼材品質關鍵技術之一。
故本研究分別針對加熱爐內所使用之燃燒器型式進行研究分析，使用傳統式燃燒器之加熱爐是利用煙道出口處之復熱器進行廢熱回收，將進口空氣預熱，則空氣溫度為定值；而使用蓄熱式燃燒器之加熱爐是利用燃燒器前段之蓄熱器進行廢熱回收，將進口空氣預熱，則空氣溫度為爐溫之函數，故蓄熱式燃燒器相較於傳統式燃燒器可提高預熱空氣之效果，降低加熱爐使用之燃料量，以提高加熱爐能源使用效率。並利用數值分析探討蓄熱式加熱爐之熱流場分析，其中使用蓄熱式燃燒器進行廢熱回收，提高進口空氣溫度，且因加熱爐內之隔板，可使加熱爐內爐溫更加均勻，因而影響鋼胚溫度分佈之均勻性，並將其數值分析之模擬值與現場實測值進行合理性比較，並探討其鋼胚冷痕現象。此外，探討在已知鋼胚升溫曲線下，反求加熱爐在使用不同熱效率之蓄熱式燃燒器下，各爐區之燃料配比與質量流率。
最後建立一套探討蓄熱式燃燒器熱效率分析之電腦輔助設計軟體，為了瞭解加熱爐所使用的蓄熱式燃燒器之蓄熱器廢熱回收系統熱效率分析，利用數值方法 - NTU法，提供鋼廠工程師快速得到蓄熱式燃燒器性能評估(rating)分析，而此性能評估包括分別對廢氣與空氣之出口溫度與壓降進行分析，並探討蓄熱式燃燒器之熱效率。

Three-dimensional simplified simulation model investigate the furnace thermal efficiency for a walking-beam type slab heating furnace with regenerative burners. The walking-beam type heating furnace is composed of five zones, namely, flameless, preheating, first heating, second heating and soaking zones with regenerator efficiency 90 %. The furnace uses a mixture of coke oven gas as a fuel to reheat the slabs. The numerical model considers turbulent combustion reactive flow coupled with radiative heat transfer in the furnace. It is shown that with regenerator burners, the furnace thermal efficiency is 72%, which is significantly higher than that of a furnace using the conventional burner without regenerator. Comparison with the in-situ experimental data from steel company in Taiwan shows that the present heat transfer model works well for the prediction of thermal behavior of the slab in the reheating furnace with regenerator burners. The numerical predictions of the slab temperature and flue gas temperature deviations with the in-situ data are about 4% and 7%, respectively. In addition, when the slab heating curve is given, estimating the fuel mass flow rate at each zone of the reheating furnace with regenerator efficiency 90 % and 70%, respectively. Compared with the reheating furnace with regenerator efficiency 70%, the quantity of fuel reduction rate is up to 10% when the reheating furnace with regenerator efficiency 90%. Finally, development of thermal efficiency analysis in regenerative burners of a computer-aided design software. Using effectiveness-NTU method, providing engineers to quickly obtain performance analysis in regenerative burners.

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