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)(re),而(er)降低(di)了空(kong)(kong)氣(qi)加(jia)熱(re)(re)(re)(re)器(qi)內(nei)電熱(re)(re)(re)(re)元(yuan)件表(biao)面溫度(du),不僅有利于(yu)延(yan)長空(kong)(kong)氣(qi)加(jia)熱(re)(re)(re)(re)器(qi)電熱(re)(re)(re)(re)元(yuan)件的使用壽命,而(er)且(qie)使得(de)空(kong)(kong)氣(qi)電加(jia)熱(re)(re)(re)(re)器(qi)散熱(re)(re)(re)(re)損失(shi)減小,因而(er)空(kong)(kong)氣(qi)換熱(re)(re)(re)(re)器(qi)的效率提高了,但速(su)度(du)如果(guo)過大(da),使得(de)壓力(li)損失(shi)陡(dou)增(zeng),這將不利于(yu)加(jia)熱(re)(re)(re)(re)效率的提高。
2.若其它條件(jian)(jian)不(bu)變,改變表(biao)(biao)面(mian)(mian)(mian)負(fu)荷(he),空(kong)氣加熱(re)(re)器(qi)(qi)中(zhong)電熱(re)(re)元件(jian)(jian)的(de)(de)(de)(de)(de)壁溫將(jiang)呈直線變化,如果表(biao)(biao)面(mian)(mian)(mian)負(fu)荷(he)增大,電熱(re)(re)元件(jian)(jian)的(de)(de)(de)(de)(de)壁溫將(jiang)增大,這將(jiang)降低(di)空(kong)氣加熱(re)(re)器(qi)(qi)中(zhong)電熱(re)(re)元件(jian)(jian)的(de)(de)(de)(de)(de)使用壽命(ming),但是如果表(biao)(biao)面(mian)(mian)(mian)負(fu)荷(he)過小,壁溫過低(di),空(kong)氣加熱(re)(re)器(qi)(qi)換熱(re)(re)器(qi)(qi)的(de)(de)(de)(de)(de)效率又(you)降低(di)了(le),所以空(kong)氣加熱(re)(re)器(qi)(qi)中(zhong)電熱(re)(re)元件(jian)(jian)的(de)(de)(de)(de)(de)表(biao)(biao)面(mian)(mian)(mian)負(fu)荷(he)的(de)(de)(de)(de)(de)選擇比較重要(yao)。
3.空(kong)氣(qi)(qi)(qi)加(jia)熱(re)器(qi)中空(kong)氣(qi)(qi)(qi)終溫T2提高時,由于空(kong)氣(qi)(qi)(qi)粘性增(zeng)加(jia),氣(qi)(qi)(qi)體雷諾(nuo)數減小(xiao),使(shi)得對流換熱(re)強度(du)降低(di),空(kong)氣(qi)(qi)(qi)加(jia)熱(re)器(qi)中電(dian)熱(re)元(yuan)件(jian)的(de)表面溫度(du)同時上(shang)升,紅外碳(tan)硫分析(xi)儀使(shi)得散(san)熱(re)損失增(zeng)加(jia),從而降低(di)換熱(re)器(qi)的(de)效率(lv)。當(dang)T2提高過大時,電(dian)熱(re)元(yuan)件(jian)表面的(de)溫度(du)亦(yi)會大大升高,致使(shi)一般電(dian)熱(re)元(yuan)件(jian)無法承受,故(gu)T2的(de)增(zeng)加(jia)通常受到空(kong)氣(qi)(qi)(qi)加(jia)熱(re)器(qi)中電(dian)熱(re)元(yuan)件(jian)材料耐熱(re)性能的(de)限(xian)制。