生物制气-柴油双燃料发动机三维燃烧模拟

Three-dimension Simulation on Combustion Process in a Biogas Diesel Dual-fuel Engine

以引燃柴油喷雾混合、燃烧化学反应机理、湍流运动、NOx预测模型、初始及边界条件设定和计算网格划分为主要内容,建立了生物制气-柴油双燃料发动机的三维燃烧模型。生物制气由气化炉热解气化各种农林废弃的生物质产生,双燃料发动机由单缸、四冲程、水冷、直喷式柴油机改装,生物制气通入发动机进气管,在进气过程中吸入气缸,由柴油引燃。计算了多个工况双燃料发动机的燃烧过程及NOx排放,并与机刨花热解制气双燃料发动机试验结果进行对比分析。结果表明气缸压力及NO排放计算结果与试验结果吻合较好。

Based on pilot fuel spray and mix, combustion chemical reaction kinetic, combustion calculation theory, turbulent flow, NOx formation model, initial and boundary conditions and meshes creation, a three dimension combustion model of a biogas diesel dual-fuel engine was established in this paper. The combustion process in the biogas diesel dual-fuel engine was simulated subsequently. The biogas was made from many kinds of agricultural and forestry residues by a gasifier. The dual-fuel engine was rebuilt by a single cylinder, four-stroke, water cooled, and direct injection diesel engine. The biogas was induced to the cylinder through intake tube of the engine during intake process and ignited by diesel fuel. The simulation results were compared and analyzed with the experimental data of a biogas （ made from shavings）- diesel dual fuel engine, and the simulated characteristics of combustion pressure and NOx emissions were in consistency with the experimental ones.