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(dui)流換(huan)熱，而降(jiang)低了空(kong)氣(qi)加(jia)(jia)熱器內電熱元(yuan)件(jian)表面溫(wen)度，不僅有利(li)(li)于延長空(kong)氣(qi)加(jia)(jia)熱器電熱元(yuan)件(jian)的(de)使(shi)用壽命，而且使(shi)得空(kong)氣(qi)電加(jia)(jia)熱器散(san)熱損失減小，因而空(kong)氣(qi)換(huan)熱器的(de)效率(lv)提高(gao)了，但速度如(ru)果(guo)過大(da)，使(shi)得壓(ya)力損失陡增，這將不利(li)(li)于加(jia)(jia)熱效率(lv)的(de)提高(gao)。

     2.若其它(ta)條件(jian)(jian)不變(bian)(bian)，改(gai)變(bian)(bian)表(biao)面(mian)負荷，空(kong)氣(qi)加熱(re)(re)器(qi)(qi)(qi)中(zhong)電熱(re)(re)元(yuan)件(jian)(jian)的(de)(de)壁溫(wen)將呈(cheng)直(zhi)線(xian)變(bian)(bian)化，如果(guo)表(biao)面(mian)負荷增大，電熱(re)(re)元(yuan)件(jian)(jian)的(de)(de)壁溫(wen)將增大，這將降低(di)(di)空(kong)氣(qi)加熱(re)(re)器(qi)(qi)(qi)中(zhong)電熱(re)(re)元(yuan)件(jian)(jian)的(de)(de)使用壽(shou)命，但是如果(guo)表(biao)面(mian)負荷過(guo)小，壁溫(wen)過(guo)低(di)(di)，空(kong)氣(qi)加熱(re)(re)器(qi)(qi)(qi)換熱(re)(re)器(qi)(qi)(qi)的(de)(de)效率又降低(di)(di)了，所以空(kong)氣(qi)加熱(re)(re)器(qi)(qi)(qi)中(zhong)電熱(re)(re)元(yuan)件(jian)(jian)的(de)(de)表(biao)面(mian)負荷的(de)(de)選擇比較重要。

     3.空(kong)(kong)(kong)氣(qi)(qi)(qi)(qi)加(jia)(jia)熱(re)(re)器中空(kong)(kong)(kong)氣(qi)(qi)(qi)(qi)終溫T2提高時，由于(yu)空(kong)(kong)(kong)氣(qi)(qi)(qi)(qi)粘(zhan)性增(zeng)(zeng)加(jia)(jia)，氣(qi)(qi)(qi)(qi)體(ti)雷諾(nuo)數減小，使得對流換熱(re)(re)強度降低(di)，空(kong)(kong)(kong)氣(qi)(qi)(qi)(qi)加(jia)(jia)熱(re)(re)器中電熱(re)(re)元件(jian)(jian)的(de)表面溫度同時上升(sheng)，紅外(wai)碳硫(liu)分析儀使得散(san)熱(re)(re)損(sun)失(shi)增(zeng)(zeng)加(jia)(jia)，從而降低(di)換熱(re)(re)器的(de)效率。當T2提高過大時，電熱(re)(re)元件(jian)(jian)表面的(de)溫度亦會大大升(sheng)高，致使一般電熱(re)(re)元件(jian)(jian)無法承受(shou)，故T2的(de)增(zeng)(zeng)加(jia)(jia)通常(chang)受(shou)到空(kong)(kong)(kong)氣(qi)(qi)(qi)(qi)加(jia)(jia)熱(re)(re)器中電熱(re)(re)元件(jian)(jian)材料耐熱(re)(re)性能的(de)限制。