【作者】 邓仁杰； 郑雷； 邓俊； 金少也； 丁伟奇； 张立军； 李理光；

【Author】 Deng Renjie;Zheng Lei;Deng Jun;Jin Shaoye;Ding Weiqi;Zhang Lijun;Li Liguang;School of Automotive Studies,Tongji University;

【机构】 同济大学汽车学院；

【摘要】 本文通过三维仿真,研究了低散热涂层厚度、材料导热系数和体积比热容对氩气动力循环发动机燃烧室壁面隔热能力和性能的影响。结果表明,在氩氧比例为9:1、转速为1000r/min、过量氧气系数为1、低散热涂层材料喷涂厚度为0.1mm时,可将燃烧阶段的壁面温度峰值提高120K,降低壁面4%的传热量,使氩气动力循环发动机的指示热效率增加1%。随着低散热材料厚度的增大,发动机的传热损失逐渐降低,指示热效率不断提高。当厚度为20mm时,指示热效率增加4.6%;厚度为50mm时,指示热效率增加8.6%。降低材料导热系数和体积比热容可同时增强壁面的隔热能力,当涂层厚度为0.5mm时,涂层材料的热物性参数和空气相当时能实现绝热燃烧,此时指示热效率可达64.7%。较大的导热系数下,降低材料体积比热容或增大低散热材料厚度对增强燃烧室壁面的隔热效果不明显,因此现阶段低散热材料的发展重点应为降低导热系数。更多还原

【Abstract】 In this paper,thr-ough three-dimensional simulation,the influence of thermal barrier coating thickness,material thermal conductivity,and volumetric specific heat capacity on the heat insulation effect of the combustion chamber wall and the influence on the energy distribution and combustion characteristics of the argon power cycle engine are studied.When the ratio of argon is 90%,the rotation speed is 1000 r/min,the excess oxygen coefficient is 1,and the thickness of the thermal barrier coating is 0.5 mm,the result shows that the peak temperature of the wall surface during the combustion phase can be increased by 120 K,the heat transf’er of the wall surface can be reduced by 4%,and the indicated Thermal efficiency of the argon power cycle engine can be increased from 49.2%to 50.2%.As the thickness of the Thermal barrier coating increases,the heat transfer loss of the engine gradually decreases,and the indicated thermal efficiency increases.When the coating thickness is 20 mm,the indicated Thermal efficiency is increased by 4.6%,and when the coating thickness is 50 mm,the indicated Thermal efficiency is increased by 8.6 %.Reducing the Thermal conductivity and volumetric specific heat capacity of the material can simultaneously enhance the thermal insulation capability of the wall.When Thermal barrier coating thickness is 0.5 mm,the thermal properties of the coating material are comparable to those of air,adiabatic combustion can be achieved,and the indicated Thermal efficiency is 64.7%.With a larger thermal conductivity,reducing the volume-specific heat capacity of the material or increasing the thickness of the coating has little effect on enhancing the thermnal insulation effect of the combustion chamber wall.Therefore,the focus of the development of Thermal barrier coating materials at this phase should be to reduce their Thermal conductivity.更多还原