Combustion chamber of direct injection diesel engine for reducing the NOx
View Patent ↗Disclosed is a combustion chamber of a diesel engine provided with a bowl having a concave shape so that fuel injected from an injector creates a swirl or squishing flow to be mixed with air, and the combustion chamber of the diesel engine includes: a pip protruding from a center of a lower surface of the bowl toward the injector; a lip part protruding from a side surface of the bowl toward the injector; and a main combustion chamber provided on a lower portion of the lip part and a sub combustion chamber provided on an upper portion of the lip part, with the lip part interposed therebetween, in which a surface of the sub combustion chamber is formed in a flat shape or a concave bowl shape to have a depth of the sub combustion chamber of 0.8 mm or lower.
1. A combustion chamber of a diesel engine provided with a bowl having a concave shape so that fuel injected from an injector is mixed with air, the combustion chamber comprising:
a pip protruding from a center of a lower surface of the bowl toward the injector;
a lip part protruding from a side surface of the bowl toward the injector; and
a main combustion chamber provided on a lower portion of the lip part and a sub combustion chamber provided on an upper portion of the lip part, with the lip part interposed therebetween,
wherein a surface of the sub combustion chamber is formed in a concave bowl shape optimized to reduce generation of nitrogen oxide by causing the fuel injected from the injector to swirl and squish by having a depth of the sub combustion chamber of 1.0 mm or lower.
2. The combustion chamber of claim 1 , wherein the depth of the sub combustion chamber is equal to or lower than 0.8 mm.
3. The combustion chamber of claim 2 , wherein the depth of the sub combustion chamber is 0.2 mm to 0.8 mm.
4. The combustion chamber of claim 1 , wherein a diameter of the lip part is smaller than a maximum diameter of the main combustion chamber, and the maximum diameter of the main combustion chamber is smaller than a diameter of an entrance of the combustion chamber.
5. The combustion chamber of claim 1 , wherein a ratio of a lip curvature center depth of the lip part to a combustion chamber maximum depth of the main combustion chamber is 2.2 to 2.8.