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(huan)熱(re)，而降低了(le)空(kong)(kong)氣(qi)加(jia)熱(re)器內電熱(re)元(yuan)件表面溫度(du)，不僅有利于延(yan)長空(kong)(kong)氣(qi)加(jia)熱(re)器電熱(re)元(yuan)件的(de)使(shi)(shi)用壽命，而且使(shi)(shi)得空(kong)(kong)氣(qi)電加(jia)熱(re)器散(san)熱(re)損失減小，因而空(kong)(kong)氣(qi)換(huan)熱(re)器的(de)效率(lv)(lv)提高(gao)了(le)，但速度(du)如果過大，使(shi)(shi)得壓力損失陡增(zeng)，這(zhe)將不利于加(jia)熱(re)效率(lv)(lv)的(de)提高(gao)。

     2.若其(qi)它(ta)條件(jian)(jian)不變(bian)，改變(bian)表(biao)面負荷，空(kong)氣(qi)加熱(re)(re)(re)器中(zhong)(zhong)電熱(re)(re)(re)元(yuan)件(jian)(jian)的(de)壁(bi)(bi)溫(wen)將呈直線變(bian)化(hua)，如果表(biao)面負荷增大，電熱(re)(re)(re)元(yuan)件(jian)(jian)的(de)壁(bi)(bi)溫(wen)將增大，這將降低(di)(di)空(kong)氣(qi)加熱(re)(re)(re)器中(zhong)(zhong)電熱(re)(re)(re)元(yuan)件(jian)(jian)的(de)使用(yong)壽命，但是如果表(biao)面負荷過(guo)小，壁(bi)(bi)溫(wen)過(guo)低(di)(di)，空(kong)氣(qi)加熱(re)(re)(re)器換熱(re)(re)(re)器的(de)效率又降低(di)(di)了，所(suo)以空(kong)氣(qi)加熱(re)(re)(re)器中(zhong)(zhong)電熱(re)(re)(re)元(yuan)件(jian)(jian)的(de)表(biao)面負荷的(de)選擇比較重(zhong)要。

     3.空(kong)氣(qi)加(jia)(jia)熱(re)(re)(re)(re)器中空(kong)氣(qi)終(zhong)溫(wen)T2提高(gao)時(shi)，由(you)于空(kong)氣(qi)粘性增加(jia)(jia)，氣(qi)體雷諾數(shu)減小(xiao)，使(shi)(shi)得對流換(huan)熱(re)(re)(re)(re)強度降(jiang)低(di)，空(kong)氣(qi)加(jia)(jia)熱(re)(re)(re)(re)器中電(dian)(dian)熱(re)(re)(re)(re)元(yuan)件(jian)的表面(mian)溫(wen)度同時(shi)上升，紅外碳(tan)硫(liu)分析儀使(shi)(shi)得散熱(re)(re)(re)(re)損失增加(jia)(jia)，從(cong)而降(jiang)低(di)換(huan)熱(re)(re)(re)(re)器的效(xiao)率。當(dang)T2提高(gao)過大時(shi)，電(dian)(dian)熱(re)(re)(re)(re)元(yuan)件(jian)表面(mian)的溫(wen)度亦會大大升高(gao)，致使(shi)(shi)一般電(dian)(dian)熱(re)(re)(re)(re)元(yuan)件(jian)無法承受，故T2的增加(jia)(jia)通常(chang)受到(dao)空(kong)氣(qi)加(jia)(jia)熱(re)(re)(re)(re)器中電(dian)(dian)熱(re)(re)(re)(re)元(yuan)件(jian)材料耐熱(re)(re)(re)(re)性能的限(xian)制。