天然气发动机涡轮增压器匹配的研究

分别搭建了柴油机和改装后的天然气发动机的工作过程计算模型。在验证模型的有效性后,进一步对天然气发动机匹配增压器进行了模拟计算。结果表明,原增压器压气机对于改装后的天然气发动机流量偏大,外特性运行工况点大部分都在压气机的低效区域运行。通过计算匹配了新增压器,使天然气发动机的平均功率比采用原增压器高2.59%,最大扭矩高1.67%,而且发动机的动力性能接近原柴油机水平,为天然气发动机进一步标定奠定了基础。

Research of Turbocharger Matching of CNG Engine

The working process models of a diesel engine and CNG engine modified by the diesel engine are built. After confirming model reliability, simulation calculation on the CNG engine with a turbocbarger was carried out. The results show that the compressor mass flow of primary turbocharger is larger to the CNG engine, and most operation points in external characteristics curve of the engine locate at low efficiency area. A new turbo charger is calculated. The new turbocharger can make the average power of CNG engine increase by 2.59% and the maximum torque by 1.67% compared with primary turbocharger. Moreover, the dynamic performance of CNG engine nearly achieve at the level of original diesel engine, and this can lay a foundation for further optimization of CNG engine performance.