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(huan)熱,而(er)降低了(le)空(kong)(kong)(kong)氣(qi)加熱器(qi)內電熱元(yuan)件表面溫度(du),不僅有利(li)于(yu)延長(chang)空(kong)(kong)(kong)氣(qi)加熱器(qi)電熱元(yuan)件的使用(yong)壽命,而(er)且使得空(kong)(kong)(kong)氣(qi)電加熱器(qi)散熱損失(shi)減小(xiao),因而(er)空(kong)(kong)(kong)氣(qi)換(huan)熱器(qi)的效率提(ti)高了(le),但速(su)度(du)如果(guo)過大,使得壓(ya)力損失(shi)陡增,這將(jiang)不利(li)于(yu)加熱效率的提(ti)高。
2.若其(qi)它條件不(bu)變,改變表面(mian)負(fu)(fu)荷(he)(he),空(kong)氣(qi)加(jia)熱(re)(re)(re)器(qi)中電(dian)(dian)熱(re)(re)(re)元(yuan)件的壁(bi)(bi)(bi)溫將(jiang)呈直線變化,如(ru)果表面(mian)負(fu)(fu)荷(he)(he)增大,電(dian)(dian)熱(re)(re)(re)元(yuan)件的壁(bi)(bi)(bi)溫將(jiang)增大,這將(jiang)降(jiang)低空(kong)氣(qi)加(jia)熱(re)(re)(re)器(qi)中電(dian)(dian)熱(re)(re)(re)元(yuan)件的使用壽命,但(dan)是(shi)如(ru)果表面(mian)負(fu)(fu)荷(he)(he)過小,壁(bi)(bi)(bi)溫過低,空(kong)氣(qi)加(jia)熱(re)(re)(re)器(qi)換熱(re)(re)(re)器(qi)的效率又降(jiang)低了,所(suo)以空(kong)氣(qi)加(jia)熱(re)(re)(re)器(qi)中電(dian)(dian)熱(re)(re)(re)元(yuan)件的表面(mian)負(fu)(fu)荷(he)(he)的選擇(ze)比(bi)較重要(yao)。
3.空(kong)(kong)氣(qi)(qi)加(jia)熱(re)(re)器中空(kong)(kong)氣(qi)(qi)終溫T2提高時,由于空(kong)(kong)氣(qi)(qi)粘(zhan)性(xing)增加(jia),氣(qi)(qi)體(ti)雷諾數減(jian)小,使得對流(liu)換(huan)熱(re)(re)強(qiang)度(du)降低,空(kong)(kong)氣(qi)(qi)加(jia)熱(re)(re)器中電(dian)(dian)熱(re)(re)元件的(de)(de)表(biao)面溫度(du)同時上升(sheng),紅(hong)外碳(tan)硫(liu)分析儀使得散熱(re)(re)損失增加(jia),從而降低換(huan)熱(re)(re)器的(de)(de)效率。當(dang)T2提高過大時,電(dian)(dian)熱(re)(re)元件表(biao)面的(de)(de)溫度(du)亦(yi)會大大升(sheng)高,致使一般電(dian)(dian)熱(re)(re)元件無法承受,故T2的(de)(de)增加(jia)通常(chang)受到空(kong)(kong)氣(qi)(qi)加(jia)熱(re)(re)器中電(dian)(dian)熱(re)(re)元件材(cai)料耐(nai)熱(re)(re)性(xing)能(neng)的(de)(de)限制。