離心(xin)風(feng)(feng)機(ji)是(shi)根據動(dong)能(neng)轉換(huan)為勢(shi)能(neng)的(de)原(yuan)理,利用高(gao)(gao)速旋轉的(de)葉輪將氣體加(jia)速,然后減速、改(gai)(gai)變流向,使(shi)動(dong)能(neng)轉換(huan)成(cheng)(cheng)(cheng)勢(shi)能(neng)(壓(ya)(ya)力(li))。在(zai)單級離心(xin)風(feng)(feng)機(ji)中(zhong),氣體從軸向進入(ru)葉輪,氣體流經(jing)葉輪時改(gai)(gai)變成(cheng)(cheng)(cheng)徑向,然后進入(ru)擴壓(ya)(ya)器。在(zai)擴壓(ya)(ya)器中(zhong),氣體改(gai)(gai)變了流動(dong)方向造(zao)成(cheng)(cheng)(cheng)減速,這種(zhong)減速作用將動(dong)能(neng)轉換(huan)成(cheng)(cheng)(cheng)壓(ya)(ya)力(li)能(neng)。壓(ya)(ya)力(li)增高(gao)(gao)主要發生(sheng)在(zai)葉輪中(zhong),其次(ci)發生(sheng)在(zai)擴壓(ya)(ya)過程。在(zai)多(duo)級離心(xin)風(feng)(feng)機(ji)中(zhong),用回流器使(shi)氣流進入(ru)下一葉輪,產(chan)生(sheng)更高(gao)(gao)壓(ya)(ya)力(li)。
離心(xin)風(feng)機的(de)工(gong)作原理與透平壓(ya)縮機基本相同(tong),均是由于氣體(ti)流(liu)速較低,壓(ya)力變化不大,一般不需要考離心(xin)風(feng)機慮(lv)氣體(ti)比(bi)容的(de)變化,即把氣體(ti)作為不可壓(ya)縮流(liu)體(ti)處理。
離心風機可制成右旋(xuan)(xuan)和左旋(xuan)(xuan)兩種型式.從電動機一側正(zheng)視,葉輪順時(shi)針旋(xuan)(xuan)轉(zhuan)(zhuan),稱(cheng)為(wei)右旋(xuan)(xuan)轉(zhuan)(zhuan)風機,葉輪逆(ni)時(shi)針旋(xuan)(xuan)轉(zhuan)(zhuan),稱(cheng)為(wei)左旋(xuan)(xuan)轉(zhuan)(zhuan)風機。