Internal Combustion Engines

← Back to document page

4InternalCombustionEnginesInternalcombus tionenginesaredevicesthatgenerateworkusi ngtheproductsofcom-bustionastheworkingfl uidratherthanasa ,thecombustionis carriedoutina mannerthatproduceshigh-pressurecombustio nprod-uctsthatcanbeexpandedthrougha introducesa :(1)thesparkignitionengine,whichisusedpr imarilyinautomobiles;(2)thedieselengine, whichisusedinlargevehiclesandindustrials ystemswheretheimprovementsincycleefficie ncymakeitadvantageousoverthemorecompacta ndlighter-weightsparkignitionengine;and( 3)thegasturbine, ,unburnedhydrocarbons, , , ,car-bonmonoxide, , pistonmovesupanddownina cylinder,transmittingitsmotionthrougha (topdeadcenter)B=crankanglePistonPistonr odCrankB=180 (bottomdeadcenter) ; ; ;stroke4, ,thesparkplugisfired, burningmixtureexpands, , ,highpowerisneededanda , , , 'I-,~0' ~ (f) "brakespecificfuelconsumption." ' ' , ,a ,however, , ,producingthenoisereferredtoasknock(Byet al.)

2. Compression. The intake valve is closed and the rising piston compresses the fuel­ air mixture. Nearthe top ofthe stroke, the spark plug is fired, igniting the mixture. 3. Expansion. The burning mixture expands, driving the piston down and delivering power. 4. Exhaust. The exhaust valve opens and the piston rises, expelling the burned gas

  Piston, Stroke