增压方式对高原重型天然气发动机性能研究  

Study on Performance of Highland Heavy-duty Natural Gas Engine by Pressurization Method

作　　者：张松[1] 宁德忠[1] 曹晟 潘月德 覃玉峰[1] 文涛 官维[2] Zhang Song;Ning De-zhong;Cao Sheng;Pan Yue-de;Qin Yu-feng;Wen Tao;Guan Wei(Guangxi Yuchai Machinery Co.,Ltd.,Chuangxi Yulin 537000;School of Mechanical Engineering,Guangxi University,Chuangxi Nanning 530004)

机构地区：[1]广西玉柴机器股份有限公司,广西玉林537000 [2]广西大学机械工程学院,广西南宁530004

出　　处：《内燃机与配件》2024年第14期25-28,共4页Internal Combustion Engine & Parts

基　　金：广西重点研发计划(桂科AB21220055,桂科AB22080084)。

摘　　要：国六当量重型天然气发动机普遍采用单级废气涡轮对新鲜充量进行增压,在高原低压环境下,相对较低的进气密度,单级废气涡轮增压方式无法提供工况稳定高效运行所需要的增压需求,导致发动机动力下降问题突出。为研究不同增压方式对国六当量重型天然气发动机高原性能的影响,通过发动机模拟高原台架测试,分析了单级废气涡轮增压和两级增压两种不同增压方式发动机在模拟高原低压环境下的性能表现。试验结果表明:两级增压方式可明显改善重型天然气发动机在高原低压环境下的动力下降问题。相比单级废气涡轮增压方式,在发动机安全运行的边界条件内,两级增压方式在平原环境下的功率密度可提升13.7%;2km海拔下发动机实现无功率损失,功率下降改善13%;2.5km海拔下发动机动力无损失;3km海拔下动力下降问题改善幅度较大,最大降幅由27.5%降低为10.2%。此外,高原低压环境下发动机增压器转速安全裕度的增加大大降低了增压器超速断轴问题的风险,提升了发动机运行的耐久可靠性。National six-equivalent heavy-duty natural gas engines commonly use a single-stage exhaust gas turbine to pressurize the fresh charge.Under the low-pressure environment of plateau,with relatively low intake air density,the single-stage exhaust gas turbine supercharging method is unable to provide the supercharging requirement for stable and efficient operation of the working conditions,resulting in the prominent problem of engine power degradation.In order to study the influence of different boosting methods on the plateau performance of National VI-equivalent heavy-duty natural gas engines,the performance of engines with single-stage exhaust gas turbocharging and two-stage supercharging in the simulated plateau low-pressure environment was analyzed through simulated plateau bench tests of the engines.The test results show that the two-stage supercharging method can significantly improve the power degradation problem of heavy-duty natural gas engine in plateau low-pressure environment.Compared with the single-stage exhaust gas turbocharging method,the power density of the two-stage supercharging method can be improved by 13.7%in the plain environment within the boundary conditions of safe engine operation;the engine realizes no power loss at 2km altitude,and the power drop is improved by 13%;there is no loss of power in the engine at 2.5km altitude,and the torque is recovered by 17%;the power drop is improved by a larger extent at 3km altitude,and the maximum drop is reduced by 27.5%to 10.5%.27.5%to 10.2%.In addition,the increase of the safety margin of the engine supercharger speed under the low-pressure environment of plateau greatly reduces the risk of supercharger over-speed shaft breakage,and improves the durability and reliability of engine operation.

关 键 词：当量天然气发动机 高原环境 增压方式 发动机性能 

分 类 号：TK421.1[动力工程及工程热物理—动力机械及工程]