【摘要】 基于定容燃烧弹，在与大型低速预燃室式双燃料船机相似的空间和热力学条件下，采用相似的点火过程，对主燃烧室内的射流火焰发展和引燃预混火焰的扩展历程进行光学测试；提出一种基于全网格映射，分阶段采用不同的燃烧模型的方法模拟不同燃烧阶段的火焰发展过程。基于定容装置试验数据验证了模型对燃烧火焰扩展速度预测的适用性和准确性。研究结果表明：预燃室燃油喷射量直接影响射流火焰的最大贯穿距离和火焰强度；主燃烧室内的混合气需要达到一定浓度才能被引燃。对燃烧过程的模拟，第一阶段燃烧采用均质搅拌反应器（well-stirred reactor, WSR）模型可以较为准确地模拟不同燃油喷射量下的射流发展速度和火焰射流的最大贯穿距离；第二阶段燃烧采用G方程可以较为准确地模拟火焰在各方向上的扩展速度。采用Mapping方法连接的两个模型对燃烧两个阶段的火焰扩展的整体速度具有较高的预测精度。更多还原

【Abstract】 Based on a constant volume combustion bomb(CVCB), the jet flame development process in the main combustion chamber were optically researched under similar spatial and thermodynamic conditions as a low-speed pre-chamber dual-fuel marine engine. A method based on the full-mesh mapping of different combustion models was proposed to simulate the flame development with two combustion stages. The process of flame development was simulated based on the mapping method. The applicability and accuracy of the model for combustion flame speed prediction were verified based on the experimental data of the test device.The research results show that the amount of fuel injection in the pre-chamber directly affects the maximum penetration distance of the jet flame and the flame intensity. The mixture in the main combustion chamber needs to be rich enough to be ignited. For the simulation of the combustion process, the well-stirred reactor(WSR) model was used for the first stage combustion simulation with the jet development speed and the maximum penetration distance. The G equation was used in the second stage combustion to accurately simulate the flame speed in all directions. The two models connected by the mapping method have high prediction accuracies for the overall speed of flame expansion in the two stages of combustion.更多还原