内燃兰金循环氨氢发动机热力学特征参数的模拟与分析

Simulation and Analysis of Thermodynamic Characteristic Parameters of Internal Combustion Rankine Cycle Ammonia Hydrogen Blended Fuel Engine

摘要:

为实现氨氢燃料在内燃机上的应用，基于Cantera平台建立了氨氢燃料内燃兰金循环模型，进行了不同氨氢掺混比例、过量空气系数和喷水量等条件下内燃兰金循环氨氢燃料发动机燃烧过程数值模拟，从热力学循环效率和典型污染物排放两方面分析和评价不同边界条件对燃烧特性的影响。结果表明：过量空气系数和缸内喷水量增加分别提升热力学循环效率2.66%和7.00%，喷水的作用效果更显著；氨氢燃料燃烧终了排放污染物NO_x主要以NO为主；缸内喷水有利于氨氢发动机氮氧化物排放量降低，应用喷水技术后，燃烧产物中NO和NO₂的排放体积分数降低幅度达到37%。

Abstract:

To realize the application of NH₃/H₂ blended fuel in internal combustion engines， an internal combustion Rankine cycle model of NH₃ / H₂ blended fuel was established in this paper based on Cantera. Additionally， the numerical simulation of combustion process of internal combustion Rankine cycle NH₃ / H₂ blended fuel engine under the conditions of different ammonia hydrogen mixing ratios， excess air ratios， and water spray volumes was conducted. Finally， the influence of different boundary conditions on combustion characteristics was analyzed from the perspectives of thermodynamic cycle efficiency and typical pollutant emissions. The results show that the increase of excess air ratio and in cylinder water spray volume improve the thermodynamic cycle efficiency by 2.66% and 7.00% respectively， hence the effect of water spray is more significant. Besides， NO is the main NO_x pollutant emitted at the end of fuel combustion. Water spray in the cylinder is beneficial to the reduction of NO_x emissions. After the application of the water spray technology， the emission of NO and NO₂ in combustion products is reduced by 37%.