汽(qi)車(che)(che)(che)要(yao)跑得快，就必須要(yao)有(you)(you)(you)強勁(jing)的(de)動(dong)(dong)力(li)。目前汽(qi)車(che)(che)(che)的(de)動(dong)(dong)力(li)系統(tong)(tong)可(ke)粗分為(wei)自(zi)然(ran)進氣(qi)(qi)系統(tong)(tong)及增(zeng)壓(ya)(ya)進氣(qi)(qi)系統(tong)(tong)兩大類。在歐洲跑車(che)(che)(che)中(zhong)，除了(le)寶馬汽(qi)車(che)(che)(che)公司(si)依(yi)然(ran)堅持使用(yong)自(zi)然(ran)進氣(qi)(qi)發動(dong)(dong)機(ji)外(wai)，其他各汽(qi)車(che)(che)(che)公司(si)為(wei)了(le)提升車(che)(che)(che)輛的(de)動(dong)(dong)力(li)性(xing)能，紛紛采用(yong)增(zeng)壓(ya)(ya)系統(tong)(tong)，例(li)如：奔馳跑車(che)(che)(che)使用(yong)機(ji)械增(zeng)壓(ya)(ya)系統(tong)(tong)，紳寶汽(qi)車(che)(che)(che)則為(wei)渦輪(lun)增(zeng)壓(ya)(ya)的(de)開(kai)山鼻祖。近年日系汽(qi)車(che)(che)(che)也開(kai)始(shi)大量采用(yong)渦輪(lun)增(zeng)壓(ya)(ya)技術。自(zi)然(ran)進氣(qi)(qi)系統(tong)(tong)沒(mei)有(you)(you)(you)安(an)裝任何形式的(de)增(zeng)壓(ya)(ya)器，只是利用(yong)活(huo)塞(sai)下行所(suo)產生的(de)負壓(ya)(ya)來吸進混(hun)合(he)氣(qi)(qi)。雖然(ran)自(zi)然(ran)進氣(qi)(qi)系統(tong)(tong)通過可(ke)變氣(qi)(qi)門(men)正時系統(tong)(tong)能夠得到較大的(de)馬力(li)輸(shu)(shu)出(chu)，但動(dong)(dong)力(li)的(de)提升很有(you)(you)(you)限。為(wei)了(le)有(you)(you)(you)效增(zeng)加發動(dong)(dong)機(ji)的(de)輸(shu)(shu)出(chu)功率，采用(yong)增(zeng)壓(ya)(ya)系統(tong)(tong)可(ke)說是最有(you)(you)(you)效的(de)方式。

最常見的發動機增壓(ya)系統有機械增壓(ya)與廢氣(qi)渦輪增壓(ya)兩種(zhong)。

機械增壓

發(fa)(fa)動(dong)機(ji)(ji)(ji)(ji)以機(ji)(ji)(ji)(ji)械(xie)(xie)方(fang)式驅(qu)動(dong)機(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)進行增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)，稱為機(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)。當發(fa)(fa)動(dong)機(ji)(ji)(ji)(ji)采(cai)用(yong)(yong)機(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)時，通常(chang)由發(fa)(fa)動(dong)機(ji)(ji)(ji)(ji)曲軸通過齒輪(lun)(lun)驅(qu)動(dong)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)。增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)一(yi)般(ban)采(cai)用(yong)(yong)離心(xin)式或羅茨(ci)壓(ya)(ya)(ya)(ya)(ya)(ya)氣機(ji)(ji)(ji)(ji)，個(ge)別的(de)采(cai)用(yong)(yong)螺桿式壓(ya)(ya)(ya)(ya)(ya)(ya)氣機(ji)(ji)(ji)(ji)。近年(nian)來(lai)(lai)，在國外也開(kai)始采(cai)用(yong)(yong)新型的(de)機(ji)(ji)(ji)(ji)械(xie)(xie)渦(wo)旋(xuan)式增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)。因(yin)為驅(qu)動(dong)壓(ya)(ya)(ya)(ya)(ya)(ya)氣機(ji)(ji)(ji)(ji)消耗了發(fa)(fa)動(dong)機(ji)(ji)(ji)(ji)一(yi)定的(de)輸(shu)出(chu)功(gong)率(lv)(lv)，所以機(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)發(fa)(fa)動(dong)機(ji)(ji)(ji)(ji)的(de)熱效率(lv)(lv)不(bu)(bu)(bu)一(yi)定得(de)到(dao)改善，有(you)(you)時反而比非增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)內燃(ran)機(ji)(ji)(ji)(ji)還(huan)低些。選擇增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)壓(ya)(ya)(ya)(ya)(ya)(ya)力時，首(shou)先(xian)要保證能(neng)達(da)到(dao)所要求的(de)平(ping)均(jun)有(you)(you)效壓(ya)(ya)(ya)(ya)(ya)(ya)力，其次(ci)要獲得(de)盡可能(neng)低的(de)燃(ran)油(you)消耗率(lv)(lv)。擔這兩(liang)(liang)個(ge)要求對于機(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)來(lai)(lai)說(shuo)常(chang)常(chang)是相互矛盾的(de)。如果追(zhui)求平(ping)均(jun)有(you)(you)效壓(ya)(ya)(ya)(ya)(ya)(ya)力，則必然導致機(ji)(ji)(ji)(ji)械(xie)(xie)效率(lv)(lv)降(jiang)低，燃(ran)油(you)消耗率(lv)(lv)升高。因(yin)此(ci)，增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)壓(ya)(ya)(ya)(ya)(ya)(ya)力值的(de)選取應(ying)在功(gong)率(lv)(lv)和燃(ran)油(you)消耗率(lv)(lv)兩(liang)(liang)者之間尋求最(zui)佳的(de)妥協(xie)方(fang)案。機(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)系統(tong)目前在歐洲車(che)上用(yong)(yong)得(de)較普遍。由于機(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)的(de)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)機(ji)(ji)(ji)(ji)是在曲軸的(de)帶(dai)動(dong)下持續地運(yun)轉，因(yin)此(ci)不(bu)(bu)(bu)動(dong)產生像(xiang)渦(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)的(de)渦(wo)輪(lun)(lun)遲滯現象。機(ji)(ji)(ji)(ji)械(xie)(xie)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)雖然只能(neng)提(ti)升約(yue)10%20%的(de)動(dong)力輸(shu)出(chu)，但平(ping)順連(lian)續性是渦(wo)輪(lun)(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)(ya)(ya)(ya)(ya)發(fa)(fa)動(dong)機(ji)(ji)(ji)(ji)所不(bu)(bu)(bu)及的(de)。

廢氣渦輪增壓(ya)

利用(yong)(yong)發動(dong)(dong)(dong)機(ji)(ji)廢(fei)氣(qi)(qi)(qi)能量驅動(dong)(dong)(dong)渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)增(zeng)壓(ya)(ya)(ya)器，稱為廢(fei)氣(qi)(qi)(qi)渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)增(zeng)壓(ya)(ya)(ya)（簡稱渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)增(zeng)壓(ya)(ya)(ya)），如圖(tu)所(suo)示(shi)是(shi)廢(fei)氣(qi)(qi)(qi)渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)增(zeng)壓(ya)(ya)(ya)系統(tong)。廢(fei)氣(qi)(qi)(qi)渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)增(zeng)壓(ya)(ya)(ya)的(de)(de)特點是(shi)在渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)增(zeng)壓(ya)(ya)(ya)器和(he)發動(dong)(dong)(dong)機(ji)(ji)之間(jian)沒(mei)有(you)機(ji)(ji)械連接(jie)。它們(men)之間(jian)靠氣(qi)(qi)(qi)路相(xiang)通。因為壓(ya)(ya)(ya)氣(qi)(qi)(qi)機(ji)(ji)消(xiao)耗(hao)的(de)(de)功(gong)是(shi)渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)從廢(fei)氣(qi)(qi)(qi)中回收(shou)的(de)(de)一(yi)部分能量，所(suo)以(yi)渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)增(zeng)壓(ya)(ya)(ya)發動(dong)(dong)(dong)機(ji)(ji)不僅可(ke)(ke)(ke)以(yi)增(zeng)加(jia)(jia)發動(dong)(dong)(dong)機(ji)(ji)的(de)(de)功(gong)率(lv)，而(er)且可(ke)(ke)(ke)以(yi)提高其(qi)熱效率(lv)，降(jiang)低燃(ran)(ran)油(you)消(xiao)耗(hao)率(lv)。如果(guo)在轎車尾部看到Turbo或者T的(de)(de)標識，即(ji)表明(ming)該車采用(yong)(yong)的(de)(de)發動(dong)(dong)(dong)機(ji)(ji)是(shi)渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)增(zeng)壓(ya)(ya)(ya)的(de)(de)。渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)增(zeng)壓(ya)(ya)(ya)器實際(ji)上是(shi)臺空(kong)氣(qi)(qi)(qi)壓(ya)(ya)(ya)縮機(ji)(ji)，它是(shi)利用(yong)(yong)發動(dong)(dong)(dong)機(ji)(ji)排出(chu)的(de)(de)廢(fei)氣(qi)(qi)(qi)慣性推動(dong)(dong)(dong)渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)，渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)又帶動(dong)(dong)(dong)同軸的(de)(de)葉(xie)輪(lun)(lun)(lun)壓(ya)(ya)(ya)縮由空(kong)氣(qi)(qi)(qi)濾清器管道送(song)來的(de)(de)空(kong)氣(qi)(qi)(qi)，使(shi)空(kong)氣(qi)(qi)(qi)增(zeng)壓(ya)(ya)(ya)后進(jin)入氣(qi)(qi)(qi)缸。當發動(dong)(dong)(dong)機(ji)(ji)轉速提高，廢(fei)氣(qi)(qi)(qi)排出(chu)速度與渦(wo)(wo)(wo)(wo)輪(lun)(lun)(lun)轉速也(ye)同步(bu)提高，葉(xie)輪(lun)(lun)(lun)就壓(ya)(ya)(ya)縮更多的(de)(de)空(kong)氣(qi)(qi)(qi)進(jin)入氣(qi)(qi)(qi)缸，空(kong)氣(qi)(qi)(qi)的(de)(de)壓(ya)(ya)(ya)力(li)和(he)密度增(zeng)大可(ke)(ke)(ke)以(yi)燃(ran)(ran)燒更多的(de)(de)燃(ran)(ran)油(you)，相(xiang)應增(zeng)加(jia)(jia)油(you)量和(he)調整一(yi)下發動(dong)(dong)(dong)機(ji)(ji)的(de)(de)轉速，就可(ke)(ke)(ke)以(yi)增(zeng)加(jia)(jia)發動(dong)(dong)(dong)機(ji)(ji)的(de)(de)輸出(chu)功(gong)率(lv)。