汽(qi)(qi)車(che)要(yao)跑得(de)快(kuai)，就(jiu)必須要(yao)有(you)(you)(you)強勁的(de)動(dong)(dong)(dong)力。目前汽(qi)(qi)車(che)的(de)動(dong)(dong)(dong)力系(xi)(xi)統(tong)(tong)可(ke)粗分為自(zi)(zi)然進(jin)氣(qi)系(xi)(xi)統(tong)(tong)及增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)進(jin)氣(qi)系(xi)(xi)統(tong)(tong)兩大類。在歐洲跑車(che)中，除了寶馬汽(qi)(qi)車(che)公司依然堅持使用(yong)(yong)(yong)自(zi)(zi)然進(jin)氣(qi)發動(dong)(dong)(dong)機外，其他各汽(qi)(qi)車(che)公司為了提(ti)(ti)升(sheng)車(che)輛的(de)動(dong)(dong)(dong)力性能，紛紛采用(yong)(yong)(yong)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)系(xi)(xi)統(tong)(tong)，例如(ru)：奔馳跑車(che)使用(yong)(yong)(yong)機械增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)系(xi)(xi)統(tong)(tong)，紳寶汽(qi)(qi)車(che)則為渦(wo)輪(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)的(de)開山鼻祖。近年(nian)日系(xi)(xi)汽(qi)(qi)車(che)也開始大量采用(yong)(yong)(yong)渦(wo)輪(lun)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)技術。自(zi)(zi)然進(jin)氣(qi)系(xi)(xi)統(tong)(tong)沒有(you)(you)(you)安裝(zhuang)任(ren)何形(xing)式(shi)的(de)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)器，只是利用(yong)(yong)(yong)活塞下(xia)行所產生的(de)負壓(ya)(ya)(ya)來吸進(jin)混合氣(qi)。雖(sui)然自(zi)(zi)然進(jin)氣(qi)系(xi)(xi)統(tong)(tong)通過可(ke)變氣(qi)門正時系(xi)(xi)統(tong)(tong)能夠得(de)到較大的(de)馬力輸出，但動(dong)(dong)(dong)力的(de)提(ti)(ti)升(sheng)很有(you)(you)(you)限。為了有(you)(you)(you)效(xiao)增(zeng)(zeng)(zeng)加(jia)發動(dong)(dong)(dong)機的(de)輸出功率，采用(yong)(yong)(yong)增(zeng)(zeng)(zeng)壓(ya)(ya)(ya)系(xi)(xi)統(tong)(tong)可(ke)說是最有(you)(you)(you)效(xiao)的(de)方式(shi)。

最常見(jian)的發動機增(zeng)(zeng)(zeng)壓(ya)系統(tong)有機械增(zeng)(zeng)(zeng)壓(ya)與廢(fei)氣渦輪(lun)增(zeng)(zeng)(zeng)壓(ya)兩種。

機(ji)械增壓

發(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)(ji)以機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)方(fang)式驅(qu)動(dong)(dong)(dong)機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)器(qi)進行增(zeng)(zeng)壓(ya)(ya)(ya)(ya)，稱(cheng)為機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)。當發(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)(ji)采(cai)用(yong)機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)時，通常(chang)由(you)發(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)(ji)曲軸通過齒輪(lun)(lun)驅(qu)動(dong)(dong)(dong)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)器(qi)。增(zeng)(zeng)壓(ya)(ya)(ya)(ya)器(qi)一般采(cai)用(yong)離心式或羅(luo)茨(ci)壓(ya)(ya)(ya)(ya)氣機(ji)(ji)(ji)(ji)，個(ge)別的(de)(de)(de)(de)采(cai)用(yong)螺桿式壓(ya)(ya)(ya)(ya)氣機(ji)(ji)(ji)(ji)。近年(nian)來，在(zai)國外也開(kai)始采(cai)用(yong)新型的(de)(de)(de)(de)機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)渦旋式增(zeng)(zeng)壓(ya)(ya)(ya)(ya)器(qi)。因(yin)為驅(qu)動(dong)(dong)(dong)壓(ya)(ya)(ya)(ya)氣機(ji)(ji)(ji)(ji)消(xiao)(xiao)耗了(le)發(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)(ji)一定(ding)的(de)(de)(de)(de)輸出功(gong)率(lv)，所以機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)發(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)(ji)的(de)(de)(de)(de)熱效率(lv)不(bu)一定(ding)得(de)到改善(shan)，有時反而(er)比非增(zeng)(zeng)壓(ya)(ya)(ya)(ya)內燃機(ji)(ji)(ji)(ji)還低(di)些。選(xuan)擇增(zeng)(zeng)壓(ya)(ya)(ya)(ya)壓(ya)(ya)(ya)(ya)力(li)(li)時，首(shou)先要(yao)保(bao)證能達到所要(yao)求(qiu)的(de)(de)(de)(de)平均有效壓(ya)(ya)(ya)(ya)力(li)(li)，其次要(yao)獲得(de)盡可能低(di)的(de)(de)(de)(de)燃油(you)消(xiao)(xiao)耗率(lv)。擔這兩(liang)個(ge)要(yao)求(qiu)對于機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)來說常(chang)常(chang)是(shi)相(xiang)互矛盾的(de)(de)(de)(de)。如果追求(qiu)平均有效壓(ya)(ya)(ya)(ya)力(li)(li)，則必然導致機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)效率(lv)降(jiang)低(di)，燃油(you)消(xiao)(xiao)耗率(lv)升高。因(yin)此(ci)，增(zeng)(zeng)壓(ya)(ya)(ya)(ya)壓(ya)(ya)(ya)(ya)力(li)(li)值(zhi)的(de)(de)(de)(de)選(xuan)取應在(zai)功(gong)率(lv)和燃油(you)消(xiao)(xiao)耗率(lv)兩(liang)者之間尋求(qiu)最佳的(de)(de)(de)(de)妥協(xie)方(fang)案。機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)系(xi)統目前在(zai)歐洲車(che)上(shang)用(yong)得(de)較(jiao)普遍。由(you)于機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)的(de)(de)(de)(de)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)機(ji)(ji)(ji)(ji)是(shi)在(zai)曲軸的(de)(de)(de)(de)帶動(dong)(dong)(dong)下持續地運(yun)轉，因(yin)此(ci)不(bu)動(dong)(dong)(dong)產生像渦輪(lun)(lun)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)的(de)(de)(de)(de)渦輪(lun)(lun)遲滯現象。機(ji)(ji)(ji)(ji)械(xie)(xie)(xie)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)雖然只能提升約10%20%的(de)(de)(de)(de)動(dong)(dong)(dong)力(li)(li)輸出，但平順連續性(xing)是(shi)渦輪(lun)(lun)增(zeng)(zeng)壓(ya)(ya)(ya)(ya)發(fa)動(dong)(dong)(dong)機(ji)(ji)(ji)(ji)所不(bu)及(ji)的(de)(de)(de)(de)。

廢氣渦(wo)輪增壓

利用(yong)發(fa)動(dong)(dong)(dong)(dong)機(ji)廢氣(qi)(qi)(qi)(qi)能(neng)量(liang)驅動(dong)(dong)(dong)(dong)渦(wo)(wo)(wo)(wo)輪(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)器(qi)，稱為廢氣(qi)(qi)(qi)(qi)渦(wo)(wo)(wo)(wo)輪(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)（簡(jian)稱渦(wo)(wo)(wo)(wo)輪(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)），如(ru)圖所示是(shi)(shi)廢氣(qi)(qi)(qi)(qi)渦(wo)(wo)(wo)(wo)輪(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)系統。廢氣(qi)(qi)(qi)(qi)渦(wo)(wo)(wo)(wo)輪(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)的(de)(de)(de)(de)(de)(de)特點(dian)是(shi)(shi)在(zai)渦(wo)(wo)(wo)(wo)輪(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)器(qi)和(he)發(fa)動(dong)(dong)(dong)(dong)機(ji)之間沒有機(ji)械(xie)連接。它們之間靠氣(qi)(qi)(qi)(qi)路相(xiang)通(tong)。因(yin)為壓(ya)(ya)氣(qi)(qi)(qi)(qi)機(ji)消耗的(de)(de)(de)(de)(de)(de)功是(shi)(shi)渦(wo)(wo)(wo)(wo)輪(lun)從廢氣(qi)(qi)(qi)(qi)中回收的(de)(de)(de)(de)(de)(de)一部(bu)分能(neng)量(liang)，所以(yi)(yi)渦(wo)(wo)(wo)(wo)輪(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)發(fa)動(dong)(dong)(dong)(dong)機(ji)不(bu)僅可以(yi)(yi)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)加發(fa)動(dong)(dong)(dong)(dong)機(ji)的(de)(de)(de)(de)(de)(de)功率，而(er)且(qie)可以(yi)(yi)提(ti)(ti)高其(qi)熱效率，降低燃油消耗率。如(ru)果在(zai)轎車尾部(bu)看到(dao)Turbo或者T的(de)(de)(de)(de)(de)(de)標(biao)識(shi)，即表明該車采用(yong)的(de)(de)(de)(de)(de)(de)發(fa)動(dong)(dong)(dong)(dong)機(ji)是(shi)(shi)渦(wo)(wo)(wo)(wo)輪(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)的(de)(de)(de)(de)(de)(de)。渦(wo)(wo)(wo)(wo)輪(lun)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)器(qi)實際上是(shi)(shi)臺空(kong)氣(qi)(qi)(qi)(qi)壓(ya)(ya)縮機(ji)，它是(shi)(shi)利用(yong)發(fa)動(dong)(dong)(dong)(dong)機(ji)排出的(de)(de)(de)(de)(de)(de)廢氣(qi)(qi)(qi)(qi)慣(guan)性推動(dong)(dong)(dong)(dong)渦(wo)(wo)(wo)(wo)輪(lun)，渦(wo)(wo)(wo)(wo)輪(lun)又(you)帶(dai)動(dong)(dong)(dong)(dong)同軸(zhou)的(de)(de)(de)(de)(de)(de)葉輪(lun)壓(ya)(ya)縮由空(kong)氣(qi)(qi)(qi)(qi)濾清器(qi)管道(dao)送來的(de)(de)(de)(de)(de)(de)空(kong)氣(qi)(qi)(qi)(qi)，使空(kong)氣(qi)(qi)(qi)(qi)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)壓(ya)(ya)后(hou)進入氣(qi)(qi)(qi)(qi)缸(gang)。當發(fa)動(dong)(dong)(dong)(dong)機(ji)轉(zhuan)速提(ti)(ti)高，廢氣(qi)(qi)(qi)(qi)排出速度與(yu)渦(wo)(wo)(wo)(wo)輪(lun)轉(zhuan)速也(ye)同步提(ti)(ti)高，葉輪(lun)就壓(ya)(ya)縮更多(duo)的(de)(de)(de)(de)(de)(de)空(kong)氣(qi)(qi)(qi)(qi)進入氣(qi)(qi)(qi)(qi)缸(gang)，空(kong)氣(qi)(qi)(qi)(qi)的(de)(de)(de)(de)(de)(de)壓(ya)(ya)力(li)和(he)密度增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)大可以(yi)(yi)燃燒更多(duo)的(de)(de)(de)(de)(de)(de)燃油，相(xiang)應(ying)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)加油量(liang)和(he)調整一下發(fa)動(dong)(dong)(dong)(dong)機(ji)的(de)(de)(de)(de)(de)(de)轉(zhuan)速，就可以(yi)(yi)增(zeng)(zeng)(zeng)(zeng)(zeng)(zeng)加發(fa)動(dong)(dong)(dong)(dong)機(ji)的(de)(de)(de)(de)(de)(de)輸出功率。