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(re),而(er)降低了(le)(le)空(kong)(kong)氣加(jia)熱(re)器內電熱(re)元件表面溫(wen)度(du),不僅(jin)有利于延(yan)長空(kong)(kong)氣加(jia)熱(re)器電熱(re)元件的使用壽(shou)命,而(er)且使得空(kong)(kong)氣電加(jia)熱(re)器散熱(re)損(sun)失(shi)(shi)減小,因而(er)空(kong)(kong)氣換熱(re)器的效率(lv)提(ti)高了(le)(le),但(dan)速度(du)如果過(guo)大,使得壓力損(sun)失(shi)(shi)陡增,這(zhe)將不利于加(jia)熱(re)效率(lv)的提(ti)高。
2.若其它條件(jian)(jian)不變(bian),改變(bian)表面負(fu)荷(he),空(kong)(kong)氣(qi)加(jia)(jia)(jia)熱(re)(re)器中(zhong)電熱(re)(re)元(yuan)(yuan)件(jian)(jian)的(de)壁(bi)(bi)溫(wen)(wen)將(jiang)呈(cheng)直線(xian)變(bian)化,如果(guo)表面負(fu)荷(he)增大(da),電熱(re)(re)元(yuan)(yuan)件(jian)(jian)的(de)壁(bi)(bi)溫(wen)(wen)將(jiang)增大(da),這(zhe)將(jiang)降低空(kong)(kong)氣(qi)加(jia)(jia)(jia)熱(re)(re)器中(zhong)電熱(re)(re)元(yuan)(yuan)件(jian)(jian)的(de)使用(yong)壽命,但是(shi)如果(guo)表面負(fu)荷(he)過小,壁(bi)(bi)溫(wen)(wen)過低,空(kong)(kong)氣(qi)加(jia)(jia)(jia)熱(re)(re)器換熱(re)(re)器的(de)效率又降低了,所以空(kong)(kong)氣(qi)加(jia)(jia)(jia)熱(re)(re)器中(zhong)電熱(re)(re)元(yuan)(yuan)件(jian)(jian)的(de)表面負(fu)荷(he)的(de)選擇比較重要。
3.空(kong)氣(qi)加熱(re)(re)(re)器中(zhong)空(kong)氣(qi)終溫(wen)(wen)T2提高時(shi)(shi),由于(yu)空(kong)氣(qi)粘性(xing)增加,氣(qi)體雷諾數(shu)減(jian)小,使得(de)對(dui)流(liu)換熱(re)(re)(re)強度(du)降低,空(kong)氣(qi)加熱(re)(re)(re)器中(zhong)電(dian)熱(re)(re)(re)元件(jian)的(de)表面溫(wen)(wen)度(du)同時(shi)(shi)上升(sheng),紅外碳硫(liu)分(fen)析儀使得(de)散熱(re)(re)(re)損失增加,從而降低換熱(re)(re)(re)器的(de)效(xiao)率(lv)。當(dang)T2提高過大時(shi)(shi),電(dian)熱(re)(re)(re)元件(jian)表面的(de)溫(wen)(wen)度(du)亦會大大升(sheng)高,致使一般電(dian)熱(re)(re)(re)元件(jian)無法(fa)承(cheng)受(shou),故T2的(de)增加通常受(shou)到空(kong)氣(qi)加熱(re)(re)(re)器中(zhong)電(dian)熱(re)(re)(re)元件(jian)材料耐熱(re)(re)(re)性(xing)能的(de)限制。