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)流換熱(re)(re)，而(er)降低了空氣(qi)(qi)加(jia)熱(re)(re)器(qi)內電(dian)熱(re)(re)元(yuan)件表面溫度(du)，不僅(jin)有利(li)于延長空氣(qi)(qi)加(jia)熱(re)(re)器(qi)電(dian)熱(re)(re)元(yuan)件的(de)(de)使(shi)用壽命(ming)，而(er)且(qie)使(shi)得空氣(qi)(qi)電(dian)加(jia)熱(re)(re)器(qi)散熱(re)(re)損失(shi)減小，因而(er)空氣(qi)(qi)換熱(re)(re)器(qi)的(de)(de)效(xiao)率提高了，但速度(du)如(ru)果過大，使(shi)得壓力損失(shi)陡增，這將(jiang)不利(li)于加(jia)熱(re)(re)效(xiao)率的(de)(de)提高。

     2.若其它條件(jian)(jian)不變(bian)，改(gai)變(bian)表(biao)(biao)面(mian)負荷，空(kong)氣加(jia)熱(re)(re)器中電(dian)(dian)熱(re)(re)元(yuan)(yuan)件(jian)(jian)的(de)壁溫將呈(cheng)直(zhi)線變(bian)化，如果表(biao)(biao)面(mian)負荷增大(da)，電(dian)(dian)熱(re)(re)元(yuan)(yuan)件(jian)(jian)的(de)壁溫將增大(da)，這將降低(di)(di)空(kong)氣加(jia)熱(re)(re)器中電(dian)(dian)熱(re)(re)元(yuan)(yuan)件(jian)(jian)的(de)使用壽(shou)命，但是如果表(biao)(biao)面(mian)負荷過小，壁溫過低(di)(di)，空(kong)氣加(jia)熱(re)(re)器換熱(re)(re)器的(de)效率又降低(di)(di)了，所(suo)以空(kong)氣加(jia)熱(re)(re)器中電(dian)(dian)熱(re)(re)元(yuan)(yuan)件(jian)(jian)的(de)表(biao)(biao)面(mian)負荷的(de)選擇比較重要(yao)。

     3.空(kong)(kong)(kong)氣(qi)加熱(re)器中(zhong)空(kong)(kong)(kong)氣(qi)終溫(wen)T2提高(gao)時，由(you)于空(kong)(kong)(kong)氣(qi)粘(zhan)性(xing)增(zeng)加，氣(qi)體雷諾數減小，使(shi)得對(dui)流換熱(re)強度(du)降低，空(kong)(kong)(kong)氣(qi)加熱(re)器中(zhong)電熱(re)元(yuan)件(jian)的表面溫(wen)度(du)同時上升，紅(hong)外碳硫(liu)分析儀(yi)使(shi)得散熱(re)損失(shi)增(zeng)加，從而降低換熱(re)器的效(xiao)率。當T2提高(gao)過大時，電熱(re)元(yuan)件(jian)表面的溫(wen)度(du)亦(yi)會(hui)大大升高(gao)，致使(shi)一般(ban)電熱(re)元(yuan)件(jian)無法承受，故T2的增(zeng)加通常(chang)受到空(kong)(kong)(kong)氣(qi)加熱(re)器中(zhong)電熱(re)元(yuan)件(jian)材料耐熱(re)性(xing)能(neng)的限制。