Modeling and Analysis on Mean Effective Torque of Rotors in Twin-Rotor Cylinder-Embedded Piston Engine

Abstract

Torque, as an important indicator of the engine, is the reflection of performance of cylinder-embedded piston engine. In power stroke, torque varies at different moments, so if the impact of structural parameters on torque needs to be analyzed, the values of torque in power stroke need to be added together and divide lasting time. The average effective torque is the average of the torque generated by explosive force during the entire power stroke, which overcomes the disadvantages of the instantaneous torque which can not reflect the changes in power process. Therefore, the influence of each structure size on the force transmission performance can be analyzed with maximizing the average effective torque. It is concluded that for increasing the average effective torque, the radius of the hinge center trajectory of cap R should be increased, and the length from rotating center O to the trajectory of piston H should be decreased. The length of rod L has little influence on the average effective torque. However, if there is a too large D-value between R and H, the rod may deflect seriously, so that the piston side force increases, causing the piston wear and tear. So the values of R and H should be selected with specified conditions in the design.