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(dui)流換(huan)熱(re)(re),而降(jiang)低(di)了(le)空(kong)氣(qi)(qi)加熱(re)(re)器(qi)(qi)內電(dian)熱(re)(re)元件(jian)表面溫度(du),不僅有利于延長(chang)空(kong)氣(qi)(qi)加熱(re)(re)器(qi)(qi)電(dian)熱(re)(re)元件(jian)的使(shi)用壽命,而且使(shi)得空(kong)氣(qi)(qi)電(dian)加熱(re)(re)器(qi)(qi)散熱(re)(re)損失減小,因而空(kong)氣(qi)(qi)換(huan)熱(re)(re)器(qi)(qi)的效率提高了(le),但速度(du)如(ru)果(guo)過大,使(shi)得壓力損失陡增,這將不利于加熱(re)(re)效率的提高。
2.若其它條件(jian)(jian)不變(bian),改變(bian)表(biao)面(mian)(mian)負(fu)荷,空氣(qi)(qi)(qi)加(jia)(jia)熱(re)(re)器中電(dian)熱(re)(re)元件(jian)(jian)的(de)(de)(de)壁(bi)溫將(jiang)呈(cheng)直線變(bian)化,如果表(biao)面(mian)(mian)負(fu)荷增大(da),電(dian)熱(re)(re)元件(jian)(jian)的(de)(de)(de)壁(bi)溫將(jiang)增大(da),這將(jiang)降低(di)空氣(qi)(qi)(qi)加(jia)(jia)熱(re)(re)器中電(dian)熱(re)(re)元件(jian)(jian)的(de)(de)(de)使用壽命,但(dan)是如果表(biao)面(mian)(mian)負(fu)荷過(guo)小,壁(bi)溫過(guo)低(di),空氣(qi)(qi)(qi)加(jia)(jia)熱(re)(re)器換熱(re)(re)器的(de)(de)(de)效率又(you)降低(di)了,所(suo)以(yi)空氣(qi)(qi)(qi)加(jia)(jia)熱(re)(re)器中電(dian)熱(re)(re)元件(jian)(jian)的(de)(de)(de)表(biao)面(mian)(mian)負(fu)荷的(de)(de)(de)選擇比較重(zhong)要。
3.空(kong)(kong)(kong)氣(qi)加(jia)熱器(qi)中空(kong)(kong)(kong)氣(qi)終溫(wen)(wen)T2提高時(shi),由于空(kong)(kong)(kong)氣(qi)粘(zhan)性(xing)增加(jia),氣(qi)體雷(lei)諾數減(jian)小,使得(de)對流(liu)換熱強(qiang)度(du)降低,空(kong)(kong)(kong)氣(qi)加(jia)熱器(qi)中電(dian)熱元(yuan)件(jian)的(de)表(biao)面溫(wen)(wen)度(du)同時(shi)上升,紅外碳硫分析儀使得(de)散熱損失(shi)增加(jia),從而降低換熱器(qi)的(de)效率。當T2提高過大(da)時(shi),電(dian)熱元(yuan)件(jian)表(biao)面的(de)溫(wen)(wen)度(du)亦(yi)會大(da)大(da)升高,致使一般電(dian)熱元(yuan)件(jian)無法承受,故T2的(de)增加(jia)通(tong)常受到空(kong)(kong)(kong)氣(qi)加(jia)熱器(qi)中電(dian)熱元(yuan)件(jian)材料耐熱性(xing)能的(de)限制。