汽(qi)車要跑得快，就必須要有(you)(you)(you)強勁的(de)(de)動(dong)力(li)。目前(qian)汽(qi)車的(de)(de)動(dong)力(li)系(xi)(xi)(xi)統(tong)(tong)可(ke)(ke)粗分為(wei)(wei)自然(ran)進(jin)(jin)氣(qi)(qi)系(xi)(xi)(xi)統(tong)(tong)及增(zeng)(zeng)壓(ya)進(jin)(jin)氣(qi)(qi)系(xi)(xi)(xi)統(tong)(tong)兩大類。在歐洲跑車中，除了(le)(le)寶馬(ma)汽(qi)車公(gong)司(si)依(yi)然(ran)堅持使用(yong)(yong)自然(ran)進(jin)(jin)氣(qi)(qi)發動(dong)機(ji)外，其他各汽(qi)車公(gong)司(si)為(wei)(wei)了(le)(le)提升車輛的(de)(de)動(dong)力(li)性能(neng)，紛(fen)紛(fen)采用(yong)(yong)增(zeng)(zeng)壓(ya)系(xi)(xi)(xi)統(tong)(tong)，例如：奔馳跑車使用(yong)(yong)機(ji)械增(zeng)(zeng)壓(ya)系(xi)(xi)(xi)統(tong)(tong)，紳寶汽(qi)車則為(wei)(wei)渦輪增(zeng)(zeng)壓(ya)的(de)(de)開(kai)山鼻祖。近年日系(xi)(xi)(xi)汽(qi)車也開(kai)始大量采用(yong)(yong)渦輪增(zeng)(zeng)壓(ya)技術。自然(ran)進(jin)(jin)氣(qi)(qi)系(xi)(xi)(xi)統(tong)(tong)沒有(you)(you)(you)安裝任何形式的(de)(de)增(zeng)(zeng)壓(ya)器(qi)，只是利用(yong)(yong)活(huo)塞下行所(suo)產生的(de)(de)負壓(ya)來吸(xi)進(jin)(jin)混(hun)合氣(qi)(qi)。雖然(ran)自然(ran)進(jin)(jin)氣(qi)(qi)系(xi)(xi)(xi)統(tong)(tong)通過可(ke)(ke)變氣(qi)(qi)門正時(shi)系(xi)(xi)(xi)統(tong)(tong)能(neng)夠(gou)得到較大的(de)(de)馬(ma)力(li)輸出，但動(dong)力(li)的(de)(de)提升很有(you)(you)(you)限。為(wei)(wei)了(le)(le)有(you)(you)(you)效增(zeng)(zeng)加發動(dong)機(ji)的(de)(de)輸出功率，采用(yong)(yong)增(zeng)(zeng)壓(ya)系(xi)(xi)(xi)統(tong)(tong)可(ke)(ke)說是最有(you)(you)(you)效的(de)(de)方式。

最常見(jian)的發(fa)動(dong)機增(zeng)壓(ya)系(xi)統(tong)有機械增(zeng)壓(ya)與廢氣渦輪增(zeng)壓(ya)兩種。

機械增壓(ya)

發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)(ji)(ji)(ji)(ji)(ji)以機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)方式(shi)驅動(dong)(dong)(dong)(dong)(dong)機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器進行增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)，稱為(wei)機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)。當發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)(ji)(ji)(ji)(ji)(ji)采(cai)(cai)用(yong)機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)時(shi)，通常由(you)發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)(ji)(ji)(ji)(ji)(ji)曲軸通過(guo)齒(chi)輪(lun)驅動(dong)(dong)(dong)(dong)(dong)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器。增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器一般采(cai)(cai)用(yong)離心式(shi)或羅茨(ci)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)氣(qi)機(ji)(ji)(ji)(ji)(ji)(ji)，個別的(de)(de)(de)采(cai)(cai)用(yong)螺(luo)桿式(shi)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)氣(qi)機(ji)(ji)(ji)(ji)(ji)(ji)。近年來，在(zai)國(guo)外也開始采(cai)(cai)用(yong)新(xin)型的(de)(de)(de)機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)渦(wo)旋式(shi)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器。因為(wei)驅動(dong)(dong)(dong)(dong)(dong)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)氣(qi)機(ji)(ji)(ji)(ji)(ji)(ji)消(xiao)(xiao)耗(hao)了發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)(ji)(ji)(ji)(ji)(ji)一定(ding)的(de)(de)(de)輸(shu)出功(gong)率(lv)，所以機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)(ji)(ji)(ji)(ji)(ji)的(de)(de)(de)熱效率(lv)不(bu)一定(ding)得(de)(de)到改善(shan)，有時(shi)反而比(bi)非增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)內燃(ran)機(ji)(ji)(ji)(ji)(ji)(ji)還低些(xie)。選擇(ze)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)力(li)(li)時(shi)，首先(xian)要(yao)保證(zheng)能達到所要(yao)求的(de)(de)(de)平均有效壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)力(li)(li)，其次要(yao)獲得(de)(de)盡(jin)可能低的(de)(de)(de)燃(ran)油消(xiao)(xiao)耗(hao)率(lv)。擔這(zhe)兩個要(yao)求對于機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)來說常常是相互矛盾的(de)(de)(de)。如果追求平均有效壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)力(li)(li)，則(ze)必然導致機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)效率(lv)降低，燃(ran)油消(xiao)(xiao)耗(hao)率(lv)升高。因此，增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)力(li)(li)值(zhi)的(de)(de)(de)選取應在(zai)功(gong)率(lv)和燃(ran)油消(xiao)(xiao)耗(hao)率(lv)兩者(zhe)之間尋求最(zui)佳的(de)(de)(de)妥協方案。機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)系統目前在(zai)歐洲車上(shang)用(yong)得(de)(de)較普遍。由(you)于機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)的(de)(de)(de)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)機(ji)(ji)(ji)(ji)(ji)(ji)是在(zai)曲軸的(de)(de)(de)帶動(dong)(dong)(dong)(dong)(dong)下持續(xu)地運轉(zhuan)，因此不(bu)動(dong)(dong)(dong)(dong)(dong)產生像渦(wo)輪(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)的(de)(de)(de)渦(wo)輪(lun)遲滯現象。機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)雖(sui)然只能提升約10%20%的(de)(de)(de)動(dong)(dong)(dong)(dong)(dong)力(li)(li)輸(shu)出，但平順連續(xu)性是渦(wo)輪(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)(ji)(ji)(ji)(ji)(ji)所不(bu)及的(de)(de)(de)。

廢氣渦輪增壓

利用(yong)發(fa)(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)廢(fei)氣(qi)(qi)能量驅動(dong)(dong)(dong)渦(wo)(wo)(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)器，稱為(wei)(wei)廢(fei)氣(qi)(qi)渦(wo)(wo)(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)（簡稱渦(wo)(wo)(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)），如(ru)圖所(suo)示是(shi)廢(fei)氣(qi)(qi)渦(wo)(wo)(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)系統。廢(fei)氣(qi)(qi)渦(wo)(wo)(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)的(de)特點是(shi)在渦(wo)(wo)(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)器和發(fa)(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)之間(jian)沒有機(ji)(ji)(ji)械連接。它(ta)們之間(jian)靠氣(qi)(qi)路相(xiang)通。因為(wei)(wei)壓(ya)(ya)(ya)氣(qi)(qi)機(ji)(ji)(ji)消(xiao)耗的(de)功(gong)是(shi)渦(wo)(wo)(wo)輪(lun)(lun)從廢(fei)氣(qi)(qi)中回(hui)收的(de)一部分能量，所(suo)以渦(wo)(wo)(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)發(fa)(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)不僅可(ke)以增(zeng)(zeng)(zeng)加(jia)發(fa)(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)的(de)功(gong)率(lv)，而且可(ke)以提(ti)高其熱效(xiao)率(lv)，降(jiang)低(di)燃油(you)消(xiao)耗率(lv)。如(ru)果在轎車(che)尾(wei)部看到Turbo或者T的(de)標識，即表明該車(che)采(cai)用(yong)的(de)發(fa)(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)是(shi)渦(wo)(wo)(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)的(de)。渦(wo)(wo)(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)器實際上是(shi)臺空氣(qi)(qi)壓(ya)(ya)(ya)縮(suo)機(ji)(ji)(ji)，它(ta)是(shi)利用(yong)發(fa)(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)排(pai)出的(de)廢(fei)氣(qi)(qi)慣性推(tui)動(dong)(dong)(dong)渦(wo)(wo)(wo)輪(lun)(lun)，渦(wo)(wo)(wo)輪(lun)(lun)又帶動(dong)(dong)(dong)同(tong)(tong)軸的(de)葉(xie)輪(lun)(lun)壓(ya)(ya)(ya)縮(suo)由空氣(qi)(qi)濾清器管道送(song)來的(de)空氣(qi)(qi)，使空氣(qi)(qi)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)后進入氣(qi)(qi)缸。當(dang)發(fa)(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)轉(zhuan)速(su)(su)提(ti)高，廢(fei)氣(qi)(qi)排(pai)出速(su)(su)度與(yu)渦(wo)(wo)(wo)輪(lun)(lun)轉(zhuan)速(su)(su)也同(tong)(tong)步提(ti)高，葉(xie)輪(lun)(lun)就(jiu)壓(ya)(ya)(ya)縮(suo)更(geng)(geng)多的(de)空氣(qi)(qi)進入氣(qi)(qi)缸，空氣(qi)(qi)的(de)壓(ya)(ya)(ya)力和密度增(zeng)(zeng)(zeng)大可(ke)以燃燒更(geng)(geng)多的(de)燃油(you)，相(xiang)應增(zeng)(zeng)(zeng)加(jia)油(you)量和調(diao)整(zheng)一下(xia)發(fa)(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)的(de)轉(zhuan)速(su)(su)，就(jiu)可(ke)以增(zeng)(zeng)(zeng)加(jia)發(fa)(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)的(de)輸出功(gong)率(lv)。