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 characte...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.展开更多
Based on theory of variable-mass system thermodynamics, the dynamic mathematic models of each component of the horizontal steam-launch system were established, and by the numerical simulation of the system launching p...Based on theory of variable-mass system thermodynamics, the dynamic mathematic models of each component of the horizontal steam-launch system were established, and by the numerical simulation of the system launching process, the thermodynamics and kinetics characteristics of the system with three valves of different flow characteristics were got. The simulation results show that the values of the peak-to-average ratios of dimensionless acceleration with the equal percentage valve, the linear valve and the quick opening valve are 1.355, 1.614 and 1.722, respectively, and the final values of the dimensionless velocities are 0.843, 0.957 and 1.0, respectively. In conclusion, the value of the dimensionless velocity with the equal percentage valve doesn't reach the set value of 0.90 when the dimensionless displacement is 0.82, while the system with the linear valve can meet the launching requirement, as well as the fluctuation range of dimensionless acceleration is less than that of the quick opening valve. Therefore, the system with the linear valve has the best performance among the three kinds of valves.展开更多
基金Project(7131109)supported by the National Defense Pre-research Foundation of ChinaProject(51175500)supported by the National Natural Science Foundation of China
文摘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.
基金Project(20080431380)supported by the National Postdoctoral Science Foundation,China
文摘Based on theory of variable-mass system thermodynamics, the dynamic mathematic models of each component of the horizontal steam-launch system were established, and by the numerical simulation of the system launching process, the thermodynamics and kinetics characteristics of the system with three valves of different flow characteristics were got. The simulation results show that the values of the peak-to-average ratios of dimensionless acceleration with the equal percentage valve, the linear valve and the quick opening valve are 1.355, 1.614 and 1.722, respectively, and the final values of the dimensionless velocities are 0.843, 0.957 and 1.0, respectively. In conclusion, the value of the dimensionless velocity with the equal percentage valve doesn't reach the set value of 0.90 when the dimensionless displacement is 0.82, while the system with the linear valve can meet the launching requirement, as well as the fluctuation range of dimensionless acceleration is less than that of the quick opening valve. Therefore, the system with the linear valve has the best performance among the three kinds of valves.