| 摘要 |
PURPOSE:To lower the specific fuel consumption and to increase the output of an engine, by mixing fuel and air effectively by dividing a combustion chamber into two sections through provision of a circumferential step on the inner wall surface of the combustion chamber so that injected fuel is separated effectively from the wall surface of the combustion chamber. CONSTITUTION:A circumferential step 8 is formed on the inner wall surface of a combustion chamber 7 so as to divide the combustion chamber 7 into an upper combustion chamber 71 and a lower combustion chamber 72 by the circumferential step 8. Fuel is injected from a nozzle 9 onto the inner wall surface of the upper combustion chamber 71, and spray of fuel thus injected is expanded in the direction S of swirl and then expanded as shown by A in the drawing. Further, the spray of fuel is separated by the step 8, and fuel flow toward the center of the combustion chamber is produced as shown by B in the drawing. On the other hand, since squish flow Q collides against the step 8, fuel flows B, C expand mainly toward the central portion of the combustion chamber 71. Therefore, it is enabled to raise the utilization factor of air in the combustion chamber 71. |
