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(huan)熱(re)(re)(re),而(er)降(jiang)低了空(kong)(kong)氣(qi)加(jia)(jia)(jia)熱(re)(re)(re)器內(nei)電(dian)(dian)熱(re)(re)(re)元件表(biao)面溫度(du),不(bu)僅有利于(yu)延長空(kong)(kong)氣(qi)加(jia)(jia)(jia)熱(re)(re)(re)器電(dian)(dian)熱(re)(re)(re)元件的(de)使(shi)用壽(shou)命,而(er)且使(shi)得空(kong)(kong)氣(qi)電(dian)(dian)加(jia)(jia)(jia)熱(re)(re)(re)器散熱(re)(re)(re)損(sun)失(shi)減小,因而(er)空(kong)(kong)氣(qi)換(huan)熱(re)(re)(re)器的(de)效(xiao)(xiao)率提高了,但(dan)速度(du)如(ru)果過大,使(shi)得壓力損(sun)失(shi)陡增(zeng),這將不(bu)利于(yu)加(jia)(jia)(jia)熱(re)(re)(re)效(xiao)(xiao)率的(de)提高。
2.若其它(ta)條件不(bu)變,改變表(biao)面(mian)(mian)負(fu)(fu)(fu)荷(he),空(kong)(kong)氣(qi)加(jia)熱(re)器中電(dian)熱(re)元(yuan)件的壁溫將(jiang)呈(cheng)直(zhi)線變化,如果(guo)表(biao)面(mian)(mian)負(fu)(fu)(fu)荷(he)增(zeng)大,電(dian)熱(re)元(yuan)件的壁溫將(jiang)增(zeng)大,這將(jiang)降低(di)(di)空(kong)(kong)氣(qi)加(jia)熱(re)器中電(dian)熱(re)元(yuan)件的使用壽命,但(dan)是如果(guo)表(biao)面(mian)(mian)負(fu)(fu)(fu)荷(he)過(guo)小,壁溫過(guo)低(di)(di),空(kong)(kong)氣(qi)加(jia)熱(re)器換熱(re)器的效率又降低(di)(di)了(le),所以空(kong)(kong)氣(qi)加(jia)熱(re)器中電(dian)熱(re)元(yuan)件的表(biao)面(mian)(mian)負(fu)(fu)(fu)荷(he)的選擇比較重(zhong)要。
3.空(kong)氣加(jia)(jia)熱(re)器中空(kong)氣終溫(wen)T2提(ti)高時(shi),由于空(kong)氣粘性增加(jia)(jia),氣體雷諾數減小,使得對流換熱(re)強度降低,空(kong)氣加(jia)(jia)熱(re)器中電熱(re)元件(jian)的表面溫(wen)度同時(shi)上升,紅外碳(tan)硫分析儀使得散熱(re)損失增加(jia)(jia),從(cong)而(er)降低換熱(re)器的效率。當T2提(ti)高過大(da)時(shi),電熱(re)元件(jian)表面的溫(wen)度亦會(hui)大(da)大(da)升高,致使一(yi)般電熱(re)元件(jian)無法承受(shou),故T2的增加(jia)(jia)通常受(shou)到空(kong)氣加(jia)(jia)熱(re)器中電熱(re)元件(jian)材料耐熱(re)性能的限制。