Mathematical modeling and analysis of thermodynamic processes in a twin-rotor piston engine

ZOU Teng-an(邹腾安), XU Hai-jun(徐海军), PAN Cun-yun(潘存云), XU Xiao-jun(徐小军), CHEN Hu(陈虎)

(College of Mechatronics Engineering and Automation,
National University of Defense Technology, Changsha 410073, China)

Abstract:In order to study the major performance indicators of the twin-rotor piston engine (TRPE), Matlab/simulink was used to simulate the mathematical models of its thermodynamic processes. With consideration of the characteristics of the working processes in the TRPE, corresponding differential equations were established and then simplified by period features of the TRPE. Finally, the major boundary conditions were figured out. The changing trends of mass, pressure and temperature of working fuel in the working chamber during a complete engine cycle were presented. The simulation results are consistent with the trends of an actual working cycle in the TRPE, which indicates that the method of simulation is feasible. As the pressure in the working chamber is calculated, all the performance parameters of the TRPE can be obtained. The major performance indicators, such as the indicated mean effective pressure, power to weight ratio and the volume power, are also acquired. Compared with three different types of conventional engines, the TRPE has a bigger utilization ratio of cylinder volume, a higher power to weight ratio and a more compact structure. This indicates that TRPE is superior to conventional engines.

Key words:twin-rotor piston engine; mathematic model; thermodynamic process; simulation; utilization ratio of cylinder volume