Gas engine and plug cover design method for gas engine

摘要

PROBLEM TO BE SOLVED: To provide a gas engine and a method for designing a plug cover in the gas engine capable of preventing misfire and deterioration in fuel economy, and allowing suitable design for effective combustion of air-fuel mixture, when an ignition chamber is provided in a combustion chamber.SOLUTION: In a gas engine 1, a plug cover 5 covering an electrode part 41 of an ignition plug 4 is protruded into a combustion chamber 30 into which air-fuel mixture M is sucked. The air-fuel mixture M sucked into the combustion chamber 30 is burned in an ignition chamber 50 and in the combustion chamber 30. In designing the plug cover 5, when a bore radius of a cylinder 11 forming the combustion chamber 30 is B (mm), a total opening area of a plurality of communication ports 521 is A (mm), internal volume of the ignition chamber 50 is C (mm), and an air excess ratio of the air-fuel mixture M sucked into the combustion chamber 30 is , A and C are determined to satisfy the following relationship; 0.45(A×B)/(C×)0.6.