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)(re),而降低了空(kong)氣(qi)(qi)(qi)(qi)加(jia)(jia)熱(re)(re)器內電熱(re)(re)元(yuan)件表(biao)面(mian)溫度,不僅有利于延長空(kong)氣(qi)(qi)(qi)(qi)加(jia)(jia)熱(re)(re)器電熱(re)(re)元(yuan)件的使用壽命(ming),而且使得空(kong)氣(qi)(qi)(qi)(qi)電加(jia)(jia)熱(re)(re)器散熱(re)(re)損失減小,因而空(kong)氣(qi)(qi)(qi)(qi)換熱(re)(re)器的效率提高(gao)(gao)了,但速(su)度如(ru)果過大,使得壓力損失陡增,這將(jiang)不利于加(jia)(jia)熱(re)(re)效率的提高(gao)(gao)。
2.若其它條件不變(bian),改變(bian)表面(mian)負(fu)荷(he),空(kong)氣(qi)加熱(re)(re)器(qi)中(zhong)電(dian)熱(re)(re)元件的(de)(de)壁(bi)溫(wen)將(jiang)(jiang)呈直(zhi)線(xian)變(bian)化,如果(guo)表面(mian)負(fu)荷(he)增(zeng)大,電(dian)熱(re)(re)元件的(de)(de)壁(bi)溫(wen)將(jiang)(jiang)增(zeng)大,這將(jiang)(jiang)降低空(kong)氣(qi)加熱(re)(re)器(qi)中(zhong)電(dian)熱(re)(re)元件的(de)(de)使用壽(shou)命,但是如果(guo)表面(mian)負(fu)荷(he)過小,壁(bi)溫(wen)過低,空(kong)氣(qi)加熱(re)(re)器(qi)換(huan)熱(re)(re)器(qi)的(de)(de)效(xiao)率又(you)降低了,所以空(kong)氣(qi)加熱(re)(re)器(qi)中(zhong)電(dian)熱(re)(re)元件的(de)(de)表面(mian)負(fu)荷(he)的(de)(de)選擇比較重要。
3.空(kong)(kong)氣(qi)加(jia)熱(re)(re)器(qi)中(zhong)空(kong)(kong)氣(qi)終溫(wen)T2提(ti)高時(shi)(shi),由于空(kong)(kong)氣(qi)粘性增加(jia),氣(qi)體雷(lei)諾數減(jian)小,使(shi)得(de)對流換(huan)熱(re)(re)強度(du)降低,空(kong)(kong)氣(qi)加(jia)熱(re)(re)器(qi)中(zhong)電(dian)(dian)熱(re)(re)元(yuan)件(jian)的(de)表面(mian)溫(wen)度(du)同時(shi)(shi)上升(sheng),紅外碳硫分析儀使(shi)得(de)散熱(re)(re)損失(shi)增加(jia),從而(er)降低換(huan)熱(re)(re)器(qi)的(de)效率(lv)。當T2提(ti)高過大時(shi)(shi),電(dian)(dian)熱(re)(re)元(yuan)件(jian)表面(mian)的(de)溫(wen)度(du)亦會(hui)大大升(sheng)高,致(zhi)使(shi)一般電(dian)(dian)熱(re)(re)元(yuan)件(jian)無法承(cheng)受,故(gu)T2的(de)增加(jia)通常受到空(kong)(kong)氣(qi)加(jia)熱(re)(re)器(qi)中(zhong)電(dian)(dian)熱(re)(re)元(yuan)件(jian)材料耐熱(re)(re)性能(neng)的(de)限(xian)制。