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熱(re),而降低了空氣(qi)加(jia)熱(re)器(qi)(qi)(qi)內電熱(re)元件表面溫度,不僅有利于(yu)延長(chang)空氣(qi)加(jia)熱(re)器(qi)(qi)(qi)電熱(re)元件的使用壽命,而且使得(de)空氣(qi)電加(jia)熱(re)器(qi)(qi)(qi)散(san)熱(re)損失減小,因(yin)而空氣(qi)換熱(re)器(qi)(qi)(qi)的效(xiao)率(lv)提(ti)高了,但速度如果過(guo)大,使得(de)壓(ya)力(li)損失陡(dou)增,這將(jiang)不利于(yu)加(jia)熱(re)效(xiao)率(lv)的提(ti)高。
2.若其(qi)它條(tiao)件(jian)不變(bian),改變(bian)表(biao)面(mian)(mian)負(fu)(fu)荷(he)(he),空(kong)氣加(jia)(jia)(jia)熱(re)(re)器(qi)(qi)(qi)(qi)(qi)中電(dian)熱(re)(re)元件(jian)的(de)壁溫(wen)將呈直(zhi)線變(bian)化,如(ru)果表(biao)面(mian)(mian)負(fu)(fu)荷(he)(he)增(zeng)大,電(dian)熱(re)(re)元件(jian)的(de)壁溫(wen)將增(zeng)大,這將降低空(kong)氣加(jia)(jia)(jia)熱(re)(re)器(qi)(qi)(qi)(qi)(qi)中電(dian)熱(re)(re)元件(jian)的(de)使用(yong)壽命(ming),但是如(ru)果表(biao)面(mian)(mian)負(fu)(fu)荷(he)(he)過(guo)小,壁溫(wen)過(guo)低,空(kong)氣加(jia)(jia)(jia)熱(re)(re)器(qi)(qi)(qi)(qi)(qi)換熱(re)(re)器(qi)(qi)(qi)(qi)(qi)的(de)效率(lv)又降低了,所以空(kong)氣加(jia)(jia)(jia)熱(re)(re)器(qi)(qi)(qi)(qi)(qi)中電(dian)熱(re)(re)元件(jian)的(de)表(biao)面(mian)(mian)負(fu)(fu)荷(he)(he)的(de)選擇比(bi)較重要。
3.空(kong)(kong)氣(qi)加(jia)(jia)熱(re)(re)(re)(re)器(qi)(qi)(qi)中空(kong)(kong)氣(qi)終溫T2提高(gao)時(shi),由于(yu)空(kong)(kong)氣(qi)粘(zhan)性增(zeng)加(jia)(jia),氣(qi)體雷(lei)諾數減小,使(shi)得對流換熱(re)(re)(re)(re)強度降低,空(kong)(kong)氣(qi)加(jia)(jia)熱(re)(re)(re)(re)器(qi)(qi)(qi)中電(dian)熱(re)(re)(re)(re)元件的表面溫度同時(shi)上升,紅外碳硫分析(xi)儀(yi)使(shi)得散熱(re)(re)(re)(re)損失增(zeng)加(jia)(jia),從(cong)而降低換熱(re)(re)(re)(re)器(qi)(qi)(qi)的效率。當T2提高(gao)過(guo)大時(shi),電(dian)熱(re)(re)(re)(re)元件表面的溫度亦會大大升高(gao),致(zhi)使(shi)一般電(dian)熱(re)(re)(re)(re)元件無法承(cheng)受,故(gu)T2的增(zeng)加(jia)(jia)通常(chang)受到空(kong)(kong)氣(qi)加(jia)(jia)熱(re)(re)(re)(re)器(qi)(qi)(qi)中電(dian)熱(re)(re)(re)(re)元件材料(liao)耐熱(re)(re)(re)(re)性能(neng)的限制。