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),而降低了(le)空氣(qi)(qi)加(jia)(jia)熱(re)器(qi)內電熱(re)元件(jian)表面溫度,不僅有(you)利于延長空氣(qi)(qi)加(jia)(jia)熱(re)器(qi)電熱(re)元件(jian)的使(shi)用(yong)壽(shou)命,而且(qie)使(shi)得(de)空氣(qi)(qi)電加(jia)(jia)熱(re)器(qi)散熱(re)損失(shi)減小,因而空氣(qi)(qi)換熱(re)器(qi)的效率(lv)提高了(le),但速度如果(guo)過大,使(shi)得(de)壓力(li)損失(shi)陡增,這將(jiang)不利于加(jia)(jia)熱(re)效率(lv)的提高。
2.若其(qi)它條件(jian)不變,改變表(biao)(biao)面負(fu)荷(he),空(kong)(kong)(kong)氣(qi)加(jia)熱(re)(re)(re)器中電(dian)熱(re)(re)(re)元(yuan)件(jian)的壁(bi)溫將呈直線變化,如果(guo)表(biao)(biao)面負(fu)荷(he)增大,電(dian)熱(re)(re)(re)元(yuan)件(jian)的壁(bi)溫將增大,這將降低(di)空(kong)(kong)(kong)氣(qi)加(jia)熱(re)(re)(re)器中電(dian)熱(re)(re)(re)元(yuan)件(jian)的使用壽命,但是如果(guo)表(biao)(biao)面負(fu)荷(he)過小,壁(bi)溫過低(di),空(kong)(kong)(kong)氣(qi)加(jia)熱(re)(re)(re)器換熱(re)(re)(re)器的效率(lv)又降低(di)了,所以空(kong)(kong)(kong)氣(qi)加(jia)熱(re)(re)(re)器中電(dian)熱(re)(re)(re)元(yuan)件(jian)的表(biao)(biao)面負(fu)荷(he)的選擇比較重要。
3.空(kong)氣(qi)加熱(re)(re)器中空(kong)氣(qi)終溫(wen)T2提高(gao)時(shi),由于(yu)空(kong)氣(qi)粘性(xing)增(zeng)加,氣(qi)體雷諾數(shu)減小,使(shi)得(de)對流換熱(re)(re)強(qiang)度降低(di),空(kong)氣(qi)加熱(re)(re)器中電(dian)熱(re)(re)元件的(de)(de)表面溫(wen)度同時(shi)上(shang)升,紅外碳硫(liu)分析儀(yi)使(shi)得(de)散熱(re)(re)損(sun)失(shi)增(zeng)加,從(cong)而降低(di)換熱(re)(re)器的(de)(de)效率。當T2提高(gao)過大(da)時(shi),電(dian)熱(re)(re)元件表面的(de)(de)溫(wen)度亦會大(da)大(da)升高(gao),致使(shi)一般電(dian)熱(re)(re)元件無法承(cheng)受,故T2的(de)(de)增(zeng)加通常受到空(kong)氣(qi)加熱(re)(re)器中電(dian)熱(re)(re)元件材(cai)料耐熱(re)(re)性(xing)能的(de)(de)限制。