폭발 릴리프 밸브가 설치된 이중연료 엔진의 급기 매니폴드에 관한 폭발 현상 해석

Abstract

As a method to reduce environmental pollutants emitted from ships, liquefied natural gas (LNG) is used as a fuel or a dual fuel engine is used. Unlike conventional diesel engines, dual fuel engines have a potential for explosion in the charge air manifold because methane-air is pre-mixed in the charge air system. In this study, to prepare a countermeasure for an explosion consequence by analyzing the charge air manifold with explosion relief valves (ERVs) intalled. In a dual fuel engine, there is a possibility that an explosion consequence may occur due to a failure during the valve overlap process. Assuming that the ignition sources were generated from the charge air valves, the explosion consequence was numerically analyzed, and the propagation of the flame and the rise in pressure were analyzed. Through this, it was possible to confirm the positions where the pressure rise were high, and the method of reducing the pressure inside the charge air manifold to less than the safety pressure by installing the ERV at these positions were analyzed. As a result of the numerical analysis, installing one ERV was not suitable for stable operation below the safety pressure of the charge air manifold. Finally, when an explosion consequence occurred in the charge air manifold, it was necessary to install two ERVs in order to reduce the pressure below the safety pressure and to ensure stable operation of the dual fuel engine. It is expected that the installation position and specifications of the ERV could be selected through the analysis of the explosion consequence of the charge air manifold of the dual fuel engine.