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)降低了空氣加熱器內(nei)電(dian)熱元件表面溫度,不僅有(you)利于延長空氣加熱器電(dian)熱元件的(de)使用壽(shou)命(ming),而(er)且使得空氣電(dian)加熱器散(san)熱損(sun)(sun)失減(jian)小,因而(er)空氣換熱器的(de)效(xiao)率提高(gao)了,但(dan)速度如果過大,使得壓力損(sun)(sun)失陡增,這(zhe)將不利于加熱效(xiao)率的(de)提高(gao)。
2.若其它(ta)條件(jian)不變,改變表(biao)面負荷(he),空氣(qi)加熱(re)器中(zhong)(zhong)電(dian)(dian)(dian)熱(re)元(yuan)件(jian)的(de)壁溫(wen)將(jiang)呈直線(xian)變化,如(ru)果表(biao)面負荷(he)增(zeng)大,電(dian)(dian)(dian)熱(re)元(yuan)件(jian)的(de)壁溫(wen)將(jiang)增(zeng)大,這將(jiang)降低空氣(qi)加熱(re)器中(zhong)(zhong)電(dian)(dian)(dian)熱(re)元(yuan)件(jian)的(de)使用(yong)壽命,但是如(ru)果表(biao)面負荷(he)過(guo)小,壁溫(wen)過(guo)低,空氣(qi)加熱(re)器換熱(re)器的(de)效率又降低了,所以(yi)空氣(qi)加熱(re)器中(zhong)(zhong)電(dian)(dian)(dian)熱(re)元(yuan)件(jian)的(de)表(biao)面負荷(he)的(de)選擇比較重要(yao)。
3.空(kong)(kong)氣加(jia)熱(re)器(qi)中(zhong)空(kong)(kong)氣終溫(wen)T2提(ti)高(gao)時(shi),由于空(kong)(kong)氣粘性增(zeng)加(jia),氣體雷諾數減(jian)小,使(shi)得(de)對流換熱(re)強度(du)降(jiang)低,空(kong)(kong)氣加(jia)熱(re)器(qi)中(zhong)電(dian)熱(re)元(yuan)件(jian)的(de)表(biao)面溫(wen)度(du)同(tong)時(shi)上升(sheng),紅外碳硫(liu)分析儀使(shi)得(de)散熱(re)損失(shi)增(zeng)加(jia),從而降(jiang)低換熱(re)器(qi)的(de)效率。當T2提(ti)高(gao)過大時(shi),電(dian)熱(re)元(yuan)件(jian)表(biao)面的(de)溫(wen)度(du)亦會大大升(sheng)高(gao),致使(shi)一(yi)般電(dian)熱(re)元(yuan)件(jian)無法承受(shou),故T2的(de)增(zeng)加(jia)通常受(shou)到空(kong)(kong)氣加(jia)熱(re)器(qi)中(zhong)電(dian)熱(re)元(yuan)件(jian)材料耐(nai)熱(re)性能(neng)的(de)限制(zhi)。