A combustion chamber and a gas engine

Abstract

The invention discloses a combustion chamber and a gas engine. The combustion chamber comprises a combustion chamber pit located at the top of a piston and sinking downwardly relative to the top of the piston, the combustion chamber pit comprises an inflow guide pit, an intermediate guide pit and a projectile guide pit which are sequentially arranged from an exhaust valve to an intake valve, the bottom surfaces of the three guide pits are sequentially an inflow guide surface, an intermediate guide surface and a projectile guide surface, the inflow guide pit and the projectile guide pit are symmetrically arranged, the inflow guide surface gradually extends downwards in the direction from the upper edge of the combustion chamber pit to the intermediate guide surface and forms a concave curved surface, and the lower ends of the inflow guide surface and the projectile guide surface are in smooth transition connection with the two sides of the projectile guide surface, and the projectile guide surface is a plane or a concave curved surface. According to the combustion chamber, the flow guide effect of each guide surface is utilized, so that the airflow is overturned upwards to form a tumble flow; and the combustion chamber pit have symmetrical features in the motion direction of the tumble flow, thereby ensuring that eddy flow and tumble flow are maintained at a higher level and improving the thermal efficiency of an engine.

Description

technical field [0001] The invention relates to the technical field of engines, in particular to a combustion chamber and a gas engine. Background technique [0002] At present, natural gas engines are generally modified on the basis of diesel engines. For a diesel engine, the vortex generated by the swirling air passage helps the oil jet to mix with the air to a certain extent, so as to achieve high-efficiency combustion and low pollutant emissions. The gas engine is mostly premixed combustion. The fuel has been mixed with the air during the intake process. After the spark plug is ignited to form a fire core, the ideal state is that there is a high turbulent kinetic energy in the cylinder during the combustion process. The increase of turbulent kinetic energy will accelerate the speed of flame propagation, which is of great significance for improving the combustion process of gas engines and reducing cycle fluctuations. If the large-scale flow of vortex continues to exist...

AI Technical Summary

Problems solved by technology

Thanks to the squish movement at the end of compression, the flame spreads faster laterally, but the flame spreads slowly in the combustion chamber 01, which is not conducive to the premixed combustion of gaseous fuels, such as figure 1 As shown, the rectangular dotted frame area near the spark plug 03 is the flame propagation low speed zone 02. The horizontal direction mentioned in this article refers to the radial direction of the cylinder, and the longitudinal direction refers to the axial direction of the cylinder.

In addition, the area 04 along the top of the piston is poorly cooled, which is an area with a high risk of knocking

In the high-speed and high-load area, the squish flow may blow out the fire core and adversely affect the ignition stability

[0004] In addition, for a gas engine transformed from a diesel engine, the intermediate air intake method and casting deviation will lead to poor consistency of swirl ratio, which in turn will lead to poor air intake consistency of each cylinder

On the premise that the valve stem cannot be tilted, although the intake port can be improved to produce a large-scale weak tumble motion in the cylinder, however, because the canopy-shaped combustion chamber similar to a gasoline engine cannot be achieved, the cylinder The tumble flow intensity is low, which is not conducive to the premixed combustion of gas fuel

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