空氣電磁加熱器影響因素
1.增大空氣加熱器的氣體入口流速,能夠加強空氣電加熱器對流換(huan)熱(re)(re)(re),而(er)降低了空(kong)氣加(jia)熱(re)(re)(re)器內(nei)電熱(re)(re)(re)元(yuan)件表(biao)面溫度,不(bu)僅有利于延長空(kong)氣加(jia)熱(re)(re)(re)器電熱(re)(re)(re)元(yuan)件的(de)使(shi)用壽命,而(er)且使(shi)得空(kong)氣電加(jia)熱(re)(re)(re)器散熱(re)(re)(re)損失減小,因而(er)空(kong)氣換(huan)熱(re)(re)(re)器的(de)效率(lv)提(ti)高了,但速(su)度如(ru)果過(guo)大,使(shi)得壓(ya)力損失陡(dou)增,這將不(bu)利于加(jia)熱(re)(re)(re)效率(lv)的(de)提(ti)高。
2.若其它條件不變(bian)(bian),改變(bian)(bian)表(biao)(biao)面(mian)負荷,空(kong)氣(qi)加熱(re)(re)(re)器(qi)中(zhong)電(dian)(dian)熱(re)(re)(re)元(yuan)件的壁(bi)溫(wen)(wen)(wen)將呈直線(xian)變(bian)(bian)化,如(ru)果表(biao)(biao)面(mian)負荷增大,電(dian)(dian)熱(re)(re)(re)元(yuan)件的壁(bi)溫(wen)(wen)(wen)將增大,這將降(jiang)低(di)空(kong)氣(qi)加熱(re)(re)(re)器(qi)中(zhong)電(dian)(dian)熱(re)(re)(re)元(yuan)件的使用壽命(ming),但(dan)是(shi)如(ru)果表(biao)(biao)面(mian)負荷過小,壁(bi)溫(wen)(wen)(wen)過低(di),空(kong)氣(qi)加熱(re)(re)(re)器(qi)換熱(re)(re)(re)器(qi)的效(xiao)率又(you)降(jiang)低(di)了,所以空(kong)氣(qi)加熱(re)(re)(re)器(qi)中(zhong)電(dian)(dian)熱(re)(re)(re)元(yuan)件的表(biao)(biao)面(mian)負荷的選(xuan)擇比較重要。
3.空氣(qi)加(jia)(jia)熱(re)(re)(re)(re)(re)器(qi)中(zhong)空氣(qi)終溫(wen)T2提高時,由于空氣(qi)粘性增加(jia)(jia),氣(qi)體(ti)雷諾數減小,使得對流換熱(re)(re)(re)(re)(re)強度降低,空氣(qi)加(jia)(jia)熱(re)(re)(re)(re)(re)器(qi)中(zhong)電(dian)熱(re)(re)(re)(re)(re)元(yuan)件的(de)表面(mian)溫(wen)度同時上升,紅外碳硫分析儀(yi)使得散(san)熱(re)(re)(re)(re)(re)損(sun)失增加(jia)(jia),從而(er)降低換熱(re)(re)(re)(re)(re)器(qi)的(de)效率。當(dang)T2提高過大時,電(dian)熱(re)(re)(re)(re)(re)元(yuan)件表面(mian)的(de)溫(wen)度亦會(hui)大大升高,致使一般電(dian)熱(re)(re)(re)(re)(re)元(yuan)件無法承受,故T2的(de)增加(jia)(jia)通常受到空氣(qi)加(jia)(jia)熱(re)(re)(re)(re)(re)器(qi)中(zhong)電(dian)熱(re)(re)(re)(re)(re)元(yuan)件材料耐熱(re)(re)(re)(re)(re)性能的(de)限制。