Lu Peng, Fang Lulu, Wang Xiangyang, Ye Qihang, Zhang Jingzhou
Key Laboratory of Thermal Environment and Structure of Ministry of Industry and Information, Jiangsu Province Key Laboratory of Aerospace Power System, College of Energy and Power Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
ACS Omega. 2019 Sep 6;4(12):15226-15233. doi: 10.1021/acsomega.9b02095. eCollection 2019 Sep 17.
In order to improve the characteristics of the air-oil two-phase flow and heat transfer in the scavenge pipe of an aero-engine bearing chamber, this paper presents several scavenge pipes with different cross-sectional geometries, by numerically investigating the processes of the air-oil two-phase flow and heat transfer, in comparison to a circular pipe. The findings indicate that the tripetal cross-section shows the best heat-transfer effect, while the four-petal cross-section has the lowest flow resistance. Under the same working condition and the equal wetted perimeter, the tripetal cross-section has an 8.8% higher heat-transfer effect than the circular section, while the four-petal cross-section has a 28.6% lower flow resistance than the circular; under the equal cross-sectional area, the tripetal cross-section has a 9.1% higher heat-transfer effect than the circular section, while the four-petal cross-section has a 23.6% lower flow resistance than the circular; under the equal hydraulic diameter, the tripetal cross-section has a 9.2% higher heat-transfer effect than the circular section, while the four-petal cross-section has a 21.9% lower flow resistance than the circular. Taking both the heat transfer and flow resistance into consideration, the four-petal cross-section exhibits the best comprehensive performance, with the comprehensive performance coefficient decreasing with the increase of oil inlet velocity and rising with the increase of air inlet velocity.
为了改善航空发动机轴承腔扫气道内气液两相流和传热特性，本文提出了几种具有不同横截面几何形状的扫气道，通过对气液两相流和传热过程进行数值研究，并与圆形管道进行比较。研究结果表明，三叶形横截面的传热效果最佳，而四叶形横截面的流动阻力最低。在相同工况和相同湿周条件下，三叶形横截面的传热效果比圆形截面高8.8%，而四叶形横截面的流动阻力比圆形低28.6%；在相同横截面积条件下，三叶形横截面的传热效果比圆形截面高9.1%，而四叶形横截面的流动阻力比圆形低23.6%；在相同水力直径条件下，三叶形横截面的传热效果比圆形截面高9.2%，而四叶形横截面的流动阻力比圆形低21.9%。综合考虑传热和流动阻力，四叶形横截面的综合性能最佳，综合性能系数随进油速度的增加而降低，随进气速度的增加而升高。
