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(liu)換熱,而(er)降低(di)了空(kong)氣加(jia)熱器(qi)內(nei)電熱元件表(biao)面溫度,不(bu)僅有(you)利于延長空(kong)氣加(jia)熱器(qi)電熱元件的(de)使用壽命(ming),而(er)且使得空(kong)氣電加(jia)熱器(qi)散(san)熱損(sun)失(shi)減小,因而(er)空(kong)氣換熱器(qi)的(de)效(xiao)率提高了,但(dan)速(su)度如果過大,使得壓力損(sun)失(shi)陡增,這將不(bu)利于加(jia)熱效(xiao)率的(de)提高。
2.若其它條件(jian)不變(bian),改變(bian)表(biao)面負(fu)荷(he),空(kong)(kong)氣(qi)加(jia)熱(re)器(qi)中電(dian)(dian)熱(re)元件(jian)的(de)(de)壁(bi)溫將(jiang)呈直(zhi)線變(bian)化(hua),如(ru)果表(biao)面負(fu)荷(he)增(zeng)大,電(dian)(dian)熱(re)元件(jian)的(de)(de)壁(bi)溫將(jiang)增(zeng)大,這將(jiang)降低(di)空(kong)(kong)氣(qi)加(jia)熱(re)器(qi)中電(dian)(dian)熱(re)元件(jian)的(de)(de)使用壽命,但(dan)是如(ru)果表(biao)面負(fu)荷(he)過小,壁(bi)溫過低(di),空(kong)(kong)氣(qi)加(jia)熱(re)器(qi)換熱(re)器(qi)的(de)(de)效率又降低(di)了,所以(yi)空(kong)(kong)氣(qi)加(jia)熱(re)器(qi)中電(dian)(dian)熱(re)元件(jian)的(de)(de)表(biao)面負(fu)荷(he)的(de)(de)選(xuan)擇比較(jiao)重(zhong)要(yao)。
3.空(kong)(kong)氣(qi)加熱(re)(re)(re)(re)器中空(kong)(kong)氣(qi)終(zhong)溫(wen)T2提高時(shi)(shi),由于空(kong)(kong)氣(qi)粘性(xing)增(zeng)加,氣(qi)體雷諾數減小,使得對流換熱(re)(re)(re)(re)強(qiang)度(du)降低(di),空(kong)(kong)氣(qi)加熱(re)(re)(re)(re)器中電熱(re)(re)(re)(re)元(yuan)件的(de)表面溫(wen)度(du)同時(shi)(shi)上升(sheng),紅(hong)外(wai)碳(tan)硫(liu)分(fen)析儀(yi)使得散熱(re)(re)(re)(re)損失增(zeng)加,從而降低(di)換熱(re)(re)(re)(re)器的(de)效率(lv)。當(dang)T2提高過大(da)時(shi)(shi),電熱(re)(re)(re)(re)元(yuan)件表面的(de)溫(wen)度(du)亦(yi)會大(da)大(da)升(sheng)高,致使一般電熱(re)(re)(re)(re)元(yuan)件無法承受(shou),故T2的(de)增(zeng)加通常受(shou)到空(kong)(kong)氣(qi)加熱(re)(re)(re)(re)器中電熱(re)(re)(re)(re)元(yuan)件材料耐熱(re)(re)(re)(re)性(xing)能的(de)限制。