Txawm hais tias nws tsuas yog "ontology qauv", lub thermal efficiency ntawm 51.09% tseem ua rau tib neeg xav tias yav tom ntej ntawm diesel xyaw. Yog tias nws tsis yog vim ob qho laj thawj ntawm kev txwv cov pa roj carbon monoxide thiab cov khoom siv hluav taws xob diesel, cov tshuab hluav taws xob yuav tsum muaj kev cia siab zoo heev. Thermal efficiency yog ib qho kev ntsuas ntawm lub zog ntawm kev ua haujlwm. Qhov siab dua qhov thermal efficiency, ntau qhov kev ua haujlwm. Kev ua haujlwm ntawm lub cav nrog thermal efficiency ntawm 35% thiab thermal efficiency ntawm 45% yog txawv kiag li.

Lub thermal efficiency ntawm roj av cav tam sim no tsuas yog nyob ib ncig ntawm 40%, thiab cov thermal efficiency yav dhau los tsuas yog nyob ib ncig ntawm 35%. Nyob rau hauv xyoo tas los no, kev nqis peev loj hauv kev tshawb fawb thiab kev tsim kho tau zoo heev txhim kho thermal efficiency, tab sis kev ua haujlwm tseem tsis zoo.

Vim qhov zoo ntawm cov qauv, cov cav diesel ua kom muaj kev sib txuas ntau dua los ntawm kev sib xyaw ua ke, thiab cov yam ntxwv ntawm homogeneous combustion ua kom combustion ntau dua. Yog li ntawd, thermal efficiency ntawm roj tsheb feem ntau yog 5% -10% siab dua li ntawm cov roj cav.