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，而降(jiang)低了空氣加熱器(qi)內(nei)電(dian)(dian)熱元件表面溫度，不僅有利于延長空氣加熱器(qi)電(dian)(dian)熱元件的(de)使用壽(shou)命，而且使得空氣電(dian)(dian)加熱器(qi)散熱損失減小(xiao)，因(yin)而空氣換熱器(qi)的(de)效(xiao)率提(ti)高(gao)了，但速度如果(guo)過大，使得壓力損失陡增(zeng)，這將不利于加熱效(xiao)率的(de)提(ti)高(gao)。

     2.若其它條件不變(bian)(bian)，改變(bian)(bian)表(biao)面負荷，空(kong)氣(qi)加熱(re)(re)器(qi)(qi)中(zhong)(zhong)電(dian)熱(re)(re)元(yuan)件的(de)壁溫將(jiang)(jiang)呈直線變(bian)(bian)化(hua)，如果表(biao)面負荷增(zeng)大，電(dian)熱(re)(re)元(yuan)件的(de)壁溫將(jiang)(jiang)增(zeng)大，這將(jiang)(jiang)降低空(kong)氣(qi)加熱(re)(re)器(qi)(qi)中(zhong)(zhong)電(dian)熱(re)(re)元(yuan)件的(de)使(shi)用壽命，但是(shi)如果表(biao)面負荷過(guo)小(xiao)，壁溫過(guo)低，空(kong)氣(qi)加熱(re)(re)器(qi)(qi)換(huan)熱(re)(re)器(qi)(qi)的(de)效率又降低了，所以空(kong)氣(qi)加熱(re)(re)器(qi)(qi)中(zhong)(zhong)電(dian)熱(re)(re)元(yuan)件的(de)表(biao)面負荷的(de)選擇比較重要。

     3.空(kong)(kong)氣(qi)加熱(re)(re)器(qi)(qi)中(zhong)空(kong)(kong)氣(qi)終溫T2提高(gao)時，由于空(kong)(kong)氣(qi)粘性(xing)增(zeng)加，氣(qi)體(ti)雷諾數減小，使(shi)得對流換熱(re)(re)強度降低，空(kong)(kong)氣(qi)加熱(re)(re)器(qi)(qi)中(zhong)電(dian)(dian)熱(re)(re)元(yuan)(yuan)件(jian)的(de)(de)表(biao)面(mian)溫度同時上升(sheng)，紅外碳硫(liu)分析(xi)儀使(shi)得散熱(re)(re)損失增(zeng)加，從而降低換熱(re)(re)器(qi)(qi)的(de)(de)效(xiao)率。當T2提高(gao)過大(da)時，電(dian)(dian)熱(re)(re)元(yuan)(yuan)件(jian)表(biao)面(mian)的(de)(de)溫度亦會大(da)大(da)升(sheng)高(gao)，致使(shi)一般電(dian)(dian)熱(re)(re)元(yuan)(yuan)件(jian)無(wu)法(fa)承(cheng)受，故T2的(de)(de)增(zeng)加通(tong)常(chang)受到空(kong)(kong)氣(qi)加熱(re)(re)器(qi)(qi)中(zhong)電(dian)(dian)熱(re)(re)元(yuan)(yuan)件(jian)材料耐(nai)熱(re)(re)性(xing)能的(de)(de)限制。