Numerical Calculation and Analysis of Friction Ignition Characteristics of Aero-Engine Titanium Alloy at Micro-Scale
MI Guangbao 1,2, LIANG Xianye 1,3, LI Peijie3 , CAO Jingxia 1,2, HUANG Xu 1,2
(1. Titanium Alloy Research Institute, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China; 2. Key Laboratory on Advanced Titanium Alloys of AECC, Beijing 100095, China; 3. National Center of Novel Materials for International Research, Tsinghua University, Beijing 100084, China)
Abstract：The abnormal friction between the vane and the casing is the main heat source of titanium fire in the aero-engine. In this paper, micro-protrusion / micro-debris of aero-engine titanium alloy friction ignition process is taken as the research object, a micro-scale ignition model considering friction heat source is established, and the influence rules of particle size, friction coefficient, oxygen concentration and flow velocity are calculated and analyzed, and compared with the classic model. The results show that the critical ignition temperature and delay time continue to decrease with decreasing particle size, increase with decreasing friction coefficient, decrease with increasing oxygen concentration, and increase with increasing flow velocity; When the particle size is 82.5μm, the critical ignition temperature of the classic model and friction model are 825K and 677K, respectively, and the ignition delay time is 0.035s and 0.032s respectively; when the friction coefficient decreases by 0.2, the critical ignition temperature increases by about 20K, the ignition delay time increase by about 10s; when the oxygen concentration reached 50%, the ignition temperatures of the classic model and friction model are 826K and 782K, respectively; when the flow velocity is 310m/s, the critical temperatures of the classic model and friction model are 966K and 964K, respectively, the ignition delay time is 0.54s and 0.43s respectively.
2020, 
