1. Stratified fuel combustion
stratified combustion has the advantage of high thermal efficiency, low throttling losses, limited as much as possible of the fuel is converted into work energy. The stratified combustion mode, the throttle valve is not fully open, ensure a certain degree of vacuum in the intake pipe (exhaust gas recirculation may be controlled and the canister etc. means). In this case, the engine torque is dependent on the size of the fuel injection amount, the intake air amount and the ignition advance angle has little relationship.
In the stratified combustion mode during an intake throttle valve opening degree is relatively large, reducing the portion of throttling losses. Key intake process is disposed in the intake manifold a replica replica open up (the principles of the nature of the actual models may vary) is sealed at the intake manifold, so that the intake air accelerated by, the Omega; shaped piston top fitting, complementary intake swirl.
stratified combustion when the fuel injection time in the top dead point before 60deg; 45deg ;, before top dead injection time has a great influence on the formation of air-fuel mixture, fuel is injected in the pit of the piston top, spray a fuel vortex is formed in conjunction with the intake air-fuel mixture. Mixture formation occurs at a crank angle 40 deg; to 50 degrees; the range, if less than this range, the mixed gas can not be ignited if it exceeds, it becomes a homogeneous state. Stratified combustion air-fuel ratio is generally between 1.6-3.
When the ignition, only around the spark plug is preferably a mixed state of gas is ignited, when the fresh air and the gas around the exhaust gas recirculation is formed from a well insulated protective, reducing the cooling cylinder arm, lift thermal efficiency. Ignition timing control is also very important, the compression only in a very narrow range ending process. .
ldquo; stratified combustion rdquo; features and advantages, difficulty
1 stratified combustion is defined as: combustion component concentration level is, the higher fuel concentration in the combustion zone center, the peripheral region is more combustion air, the end result is ldquo; complete combustion rdquo ;.
2. Require instant ignition, spark plug electrodeThe fuel vapor concentration is just in order to reliably firing. Some other regional bias does not matter; but over the years the most difficult is it!.
3 engine ldquo;. Throttled rdquo; or when idling, in-cylinder rich requires only a little fuel vapor in the spark plug region, the other region is fresh air, clean, complete combustion of fuel can be achieved.
4 due to the combustion of the final result is excess oxygen-containing air as well, can be completely thorough combustion, the engine fuel efficiency so high, poor combustion contaminants hardly a conventional engine. .
5 in the feeding cylinder fuel atomizer naturally finer the better, but the proportion of fuel than conventional engines the concentration range used in bigger, so that the ldquo; carburetor rdquo; simple adjustment to these easy to handle.
6 because ldquo;. Throttled rdquo; when the excess air combustion zone and cylinder wall, spaced apart from the piston, the engine heat is not very serious, due to less engine heat for power efficiency and improved . .
Most 7 ldquo; stratified combustion rdquo; structure of the engine spark plug is aligned with a spray nozzle fuel state, a small ignition chamber embodiment in a high concentration of fuel ignition, and then the entire diffusion combustion.
8 does not use a large number of homogenous fuel vapor without fear of large-scale fuel vapor pressure deflagration accident, it is possible to improve the engine compression ratio, it is usually good for improving the work efficiency of the engine.
9. Such a conventional combustion engine with an opposite manner, when the small throttle especially good extreme saving state, adapted to actual use with most vehicles usually more small throttle, the throttle occasionally used. .
because the cylinder 10 is filled with incomplete homogeneous fuel vapor, the engine of ldquo; l power rdquo; slightly lower, but the overall weight loss, and an increase in the engine cooling system should be substantially displacement almost.
ldquo; stratified combustion & rdquo; is reasonably applied ldquo; more gas and less oil rdquo; arrangement of the fuel combustion completely full, so certain embodiments stratified combustion in the engine is ldquo ; rdquo more gas and less oil; Basic layout. The most critical point is the most difficult: the concentration of fuel vapor to be partially accommodate the ignition spark, as long as the ignition point, the other portion of the fuel can be more or less is ldquo; throttle angle rdquo ;. Just ignition
In the heated air cylinder concentrations, somewhat similar to the cup in windy day ten meters fuel splashed to the outside of a lighted match moment, a bit more difficult. In addition to ignition problems, there are many other aspects of technical issues; overseas for decades has been a lot of experimental design structure, but has yet to perfect the engine over the standard structure appears, the difficulty can be seen.