Numerical Simulation of Mixed Scavenging Methods for Two-stroke Diesel Aero Engines
CHEN Qiangen1,2, ZHANG Xiangjian1, PAN Zhongjian1, XU Xiaolong1
1. Key State Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, China;
2. Sunward Intelligent Equipment Limited Liability Company, Changsha 410199, China
Abstract：This paper establishes a three-dimensional scavenging model and a gas flow mathematical model of the inner cylinder for one type of two-stroke diesel aero engine, and analyzes the structure of the gas ports. The calculation domain of the model is meshed by the methods of the multiple block coupling and bonding technology, and the boundary conditions are set by the GT-power. The Fluent software is applied to simulate the three-dimensional gas flow in the inner cylinder. The research results show that the cross scavenging easily produces scavenging blind spots at the weak flow area; the loop scavenging can form a preferable backflow at the radial direction, but the axial velocity is lower, decreasing the scavenging efficiency; The mixed scavenging reduces the scavenging blind spots and forms better spiral vortexes and higher axial swirls, and increases the exhaust velocity by 12.6% and 125.2%, respectively compared with the loop scavenging and the cross scavenging.
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2014, Vol. 32 
