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，而降低(di)了空(kong)(kong)(kong)氣加(jia)(jia)熱器(qi)內電熱元件表面溫度，不僅(jin)有利(li)于(yu)延長空(kong)(kong)(kong)氣加(jia)(jia)熱器(qi)電熱元件的使(shi)(shi)用壽(shou)命，而且(qie)使(shi)(shi)得(de)空(kong)(kong)(kong)氣電加(jia)(jia)熱器(qi)散熱損(sun)失(shi)減小，因而空(kong)(kong)(kong)氣換熱器(qi)的效率提高了，但速度如果(guo)過大，使(shi)(shi)得(de)壓(ya)力損(sun)失(shi)陡增，這(zhe)將不利(li)于(yu)加(jia)(jia)熱效率的提高。

     2.若其(qi)它條件不(bu)變(bian)，改變(bian)表(biao)面(mian)負荷(he)，空(kong)(kong)氣(qi)加(jia)(jia)熱(re)(re)器中電(dian)熱(re)(re)元件的(de)壁溫將(jiang)呈直線變(bian)化，如果表(biao)面(mian)負荷(he)增大，電(dian)熱(re)(re)元件的(de)壁溫將(jiang)增大，這將(jiang)降低空(kong)(kong)氣(qi)加(jia)(jia)熱(re)(re)器中電(dian)熱(re)(re)元件的(de)使用壽命，但是如果表(biao)面(mian)負荷(he)過(guo)小，壁溫過(guo)低，空(kong)(kong)氣(qi)加(jia)(jia)熱(re)(re)器換熱(re)(re)器的(de)效率(lv)又降低了，所以空(kong)(kong)氣(qi)加(jia)(jia)熱(re)(re)器中電(dian)熱(re)(re)元件的(de)表(biao)面(mian)負荷(he)的(de)選擇比較重要。

     3.空(kong)(kong)氣(qi)加(jia)熱(re)(re)器中(zhong)(zhong)空(kong)(kong)氣(qi)終溫T2提(ti)高(gao)時(shi)(shi)，由于(yu)空(kong)(kong)氣(qi)粘(zhan)性增(zeng)加(jia)，氣(qi)體雷諾數減小，使得對流換熱(re)(re)強度(du)降低，空(kong)(kong)氣(qi)加(jia)熱(re)(re)器中(zhong)(zhong)電(dian)(dian)熱(re)(re)元(yuan)件(jian)的(de)表面溫度(du)同時(shi)(shi)上升(sheng)(sheng)，紅外碳硫(liu)分(fen)析(xi)儀(yi)使得散熱(re)(re)損(sun)失(shi)增(zeng)加(jia)，從(cong)而(er)降低換熱(re)(re)器的(de)效(xiao)率。當T2提(ti)高(gao)過大時(shi)(shi)，電(dian)(dian)熱(re)(re)元(yuan)件(jian)表面的(de)溫度(du)亦會(hui)大大升(sheng)(sheng)高(gao)，致(zhi)使一般電(dian)(dian)熱(re)(re)元(yuan)件(jian)無法承受(shou)，故T2的(de)增(zeng)加(jia)通(tong)常受(shou)到空(kong)(kong)氣(qi)加(jia)熱(re)(re)器中(zhong)(zhong)電(dian)(dian)熱(re)(re)元(yuan)件(jian)材料耐熱(re)(re)性能的(de)限制(zhi)。