北京科技大学学报
北京科技大學學報
북경과기대학학보
JOURNAL OF UNIVERSITY OF SCIENCE AND TECHNOLOGY BEIJING
2014年
11期
1552-1559
,共8页
冯俊小%姜敏%周闻华%吴启明%向顺华
馮俊小%薑敏%週聞華%吳啟明%嚮順華
풍준소%강민%주문화%오계명%향순화
辐射管%流动传热%烟气%温度%氮氧化物%气体排放%数值模拟
輻射管%流動傳熱%煙氣%溫度%氮氧化物%氣體排放%數值模擬
복사관%류동전열%연기%온도%담양화물%기체배방%수치모의
radiant tubes%heat transfer%flue gas%temperature%nitrogen oxides%gas emission%numerical simulation
为解决 W 型辐射管温度均匀性差和 NOx 排放过高的问题,提出了一种新型带烟气循环的 W 型辐射管,建立了该辐射管的数学模型,并运用数值计算的方法进行了模拟研究.在验证模型可靠的基础上,对带烟气循环的 W 型辐射管和常规 W型辐射管的流场、温度场和 NOx 排放进行了比较.结果表明:带烟气循环的 W 型辐射管气体平均流速是常规 W 型辐射管气体流速的3倍,有57.6%的烟气参与再循环;带烟气循环的 W 型辐射管中气体燃烧最高温度为2260 K,比 W 型辐射管低192 K;带烟气循环的 W 型辐射管壁面温差为166 K,比常规 W 型辐射管的壁面温差小76 K;带烟气循环的 W 型辐射管的 NOx 排放量9.9×10-5,而 W 型辐射管的 NOx 排放达到7.98×10-4,高出将近7倍.
為解決 W 型輻射管溫度均勻性差和 NOx 排放過高的問題,提齣瞭一種新型帶煙氣循環的 W 型輻射管,建立瞭該輻射管的數學模型,併運用數值計算的方法進行瞭模擬研究.在驗證模型可靠的基礎上,對帶煙氣循環的 W 型輻射管和常規 W型輻射管的流場、溫度場和 NOx 排放進行瞭比較.結果錶明:帶煙氣循環的 W 型輻射管氣體平均流速是常規 W 型輻射管氣體流速的3倍,有57.6%的煙氣參與再循環;帶煙氣循環的 W 型輻射管中氣體燃燒最高溫度為2260 K,比 W 型輻射管低192 K;帶煙氣循環的 W 型輻射管壁麵溫差為166 K,比常規 W 型輻射管的壁麵溫差小76 K;帶煙氣循環的 W 型輻射管的 NOx 排放量9.9×10-5,而 W 型輻射管的 NOx 排放達到7.98×10-4,高齣將近7倍.
위해결 W 형복사관온도균균성차화 NOx 배방과고적문제,제출료일충신형대연기순배적 W 형복사관,건립료해복사관적수학모형,병운용수치계산적방법진행료모의연구.재험증모형가고적기출상,대대연기순배적 W 형복사관화상규 W형복사관적류장、온도장화 NOx 배방진행료비교.결과표명:대연기순배적 W 형복사관기체평균류속시상규 W 형복사관기체류속적3배,유57.6%적연기삼여재순배;대연기순배적 W 형복사관중기체연소최고온도위2260 K,비 W 형복사관저192 K;대연기순배적 W 형복사관벽면온차위166 K,비상규 W 형복사관적벽면온차소76 K;대연기순배적 W 형복사관적 NOx 배방량9.9×10-5,이 W 형복사관적 NOx 배방체도7.98×10-4,고출장근7배.
In order to solve the large wall temperature difference and high NOx emission of W-shaped radiant tubes, this article in-troduces a kind of W-shaped radiant tube with flue gas circulation. A mathematical model of the radiant tube is established and the ra-diant tube is studied by the method of numerical calculation. On the basis of the model’s reliability, the velocity field, temperature field and NOx emission are compared between the radiant tube and a conventional W-shaped radiant tube. The average gas velocity of the new radiant tube is three times that of the conventional radiant tube, and 57. 6% flue gas is involved in recombustion in the new ra-diant tube. The maximum combustion temperature of the new radiant tube is 2260 K, which is 192 K lower than that of the conventional radiant tube. The wall temperature difference of the new radiant tube is 166 K,which is 76 K lower than that of the conventional radiant tube. The NOx emission of the new radiant tube is 9. 9 × 10 - 5 , but the NOx emission of the conventional radiant tube is 7. 98 × 10 - 4 , nearly seven times higher.