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(re)(re)(re),而降低(di)了空氣(qi)加熱(re)(re)(re)器(qi)內電(dian)(dian)熱(re)(re)(re)元件表面溫度(du),不(bu)僅有利(li)(li)于延長空氣(qi)加熱(re)(re)(re)器(qi)電(dian)(dian)熱(re)(re)(re)元件的使(shi)用壽命,而且(qie)使(shi)得空氣(qi)電(dian)(dian)加熱(re)(re)(re)器(qi)散熱(re)(re)(re)損(sun)失(shi)減小(xiao),因(yin)而空氣(qi)換熱(re)(re)(re)器(qi)的效率提(ti)高了,但速度(du)如果過大,使(shi)得壓力損(sun)失(shi)陡增,這將不(bu)利(li)(li)于加熱(re)(re)(re)效率的提(ti)高。
2.若其它條(tiao)件(jian)(jian)不變(bian)(bian),改變(bian)(bian)表面(mian)負(fu)荷(he)(he)(he),空(kong)氣(qi)加(jia)(jia)(jia)熱(re)(re)(re)器(qi)中(zhong)(zhong)電(dian)熱(re)(re)(re)元件(jian)(jian)的壁(bi)(bi)溫將(jiang)呈直線變(bian)(bian)化,如(ru)果表面(mian)負(fu)荷(he)(he)(he)增大,電(dian)熱(re)(re)(re)元件(jian)(jian)的壁(bi)(bi)溫將(jiang)增大,這將(jiang)降低空(kong)氣(qi)加(jia)(jia)(jia)熱(re)(re)(re)器(qi)中(zhong)(zhong)電(dian)熱(re)(re)(re)元件(jian)(jian)的使用壽命,但是如(ru)果表面(mian)負(fu)荷(he)(he)(he)過(guo)小,壁(bi)(bi)溫過(guo)低,空(kong)氣(qi)加(jia)(jia)(jia)熱(re)(re)(re)器(qi)換熱(re)(re)(re)器(qi)的效率又降低了,所以空(kong)氣(qi)加(jia)(jia)(jia)熱(re)(re)(re)器(qi)中(zhong)(zhong)電(dian)熱(re)(re)(re)元件(jian)(jian)的表面(mian)負(fu)荷(he)(he)(he)的選擇比(bi)較重要。
3.空(kong)氣(qi)加(jia)熱(re)器(qi)(qi)中(zhong)空(kong)氣(qi)終溫T2提高(gao)時(shi),由于空(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)強(qiang)度降(jiang)低,空(kong)氣(qi)加(jia)熱(re)器(qi)(qi)中(zhong)電(dian)熱(re)元件(jian)的(de)表(biao)面溫度同時(shi)上(shang)升(sheng),紅(hong)外碳(tan)硫分析(xi)儀使得散熱(re)損失增(zeng)加(jia),從而(er)降(jiang)低換熱(re)器(qi)(qi)的(de)效率。當(dang)T2提高(gao)過大時(shi),電(dian)熱(re)元件(jian)表(biao)面的(de)溫度亦會大大升(sheng)高(gao),致使一(yi)般電(dian)熱(re)元件(jian)無法承受,故T2的(de)增(zeng)加(jia)通常受到空(kong)氣(qi)加(jia)熱(re)器(qi)(qi)中(zhong)電(dian)熱(re)元件(jian)材料耐熱(re)性能(neng)的(de)限制。