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)流換熱(re)(re),而(er)(er)降低了空(kong)氣加(jia)(jia)熱(re)(re)器(qi)內電(dian)(dian)熱(re)(re)元件表面溫(wen)度(du),不僅有(you)利于延(yan)長空(kong)氣加(jia)(jia)熱(re)(re)器(qi)電(dian)(dian)熱(re)(re)元件的使用(yong)壽命(ming),而(er)(er)且使得空(kong)氣電(dian)(dian)加(jia)(jia)熱(re)(re)器(qi)散熱(re)(re)損(sun)(sun)失減(jian)小,因而(er)(er)空(kong)氣換熱(re)(re)器(qi)的效率提(ti)高了,但速度(du)如果過大,使得壓力損(sun)(sun)失陡增,這將不利于加(jia)(jia)熱(re)(re)效率的提(ti)高。
2.若其它條件不變(bian),改變(bian)表(biao)面(mian)負(fu)(fu)荷(he),空氣(qi)加熱器中電(dian)熱元件的(de)(de)壁溫將(jiang)呈直(zhi)線變(bian)化(hua),如果(guo)表(biao)面(mian)負(fu)(fu)荷(he)增大,電(dian)熱元件的(de)(de)壁溫將(jiang)增大,這將(jiang)降(jiang)低空氣(qi)加熱器中電(dian)熱元件的(de)(de)使用壽命(ming),但是如果(guo)表(biao)面(mian)負(fu)(fu)荷(he)過小,壁溫過低,空氣(qi)加熱器換熱器的(de)(de)效率(lv)又降(jiang)低了,所以空氣(qi)加熱器中電(dian)熱元件的(de)(de)表(biao)面(mian)負(fu)(fu)荷(he)的(de)(de)選擇比較重要。
3.空氣(qi)(qi)(qi)加(jia)熱(re)(re)(re)(re)器(qi)(qi)中(zhong)空氣(qi)(qi)(qi)終溫T2提高時,由于空氣(qi)(qi)(qi)粘性(xing)增加(jia),氣(qi)(qi)(qi)體(ti)雷諾(nuo)數(shu)減(jian)小(xiao),使得對流換熱(re)(re)(re)(re)強度降(jiang)(jiang)低,空氣(qi)(qi)(qi)加(jia)熱(re)(re)(re)(re)器(qi)(qi)中(zhong)電(dian)(dian)熱(re)(re)(re)(re)元(yuan)件(jian)(jian)的(de)表面(mian)溫度同時上升,紅外碳硫分析(xi)儀使得散熱(re)(re)(re)(re)損(sun)失增加(jia),從而降(jiang)(jiang)低換熱(re)(re)(re)(re)器(qi)(qi)的(de)效(xiao)率。當T2提高過大時,電(dian)(dian)熱(re)(re)(re)(re)元(yuan)件(jian)(jian)表面(mian)的(de)溫度亦會大大升高,致使一般(ban)電(dian)(dian)熱(re)(re)(re)(re)元(yuan)件(jian)(jian)無(wu)法(fa)承受(shou),故T2的(de)增加(jia)通常(chang)受(shou)到空氣(qi)(qi)(qi)加(jia)熱(re)(re)(re)(re)器(qi)(qi)中(zhong)電(dian)(dian)熱(re)(re)(re)(re)元(yuan)件(jian)(jian)材料耐熱(re)(re)(re)(re)性(xing)能的(de)限制。