Mechanical Efficiency Research Of A Twin-Rotor Piston Engine

Proposed as a new engine, the double rotary piston engine’s high power density has always been its main highlight. However, this high power density is a conclusion only considering about the structural characteristics of the power cylinder, believing that within a cycle the plurality of working chambers will produce a large amount of mechanical energy, without taking the mechanical energy loss during transmission into consideration. By studying the rotary engine, this paper obtained mechanical efficiency of the engine under certain conditions, and analyzed the different factors that influence the mechanical efficiency of the engine.Focused on the mechanical efficiency of the engine, the main research contents of the paper are as follows:1) Lubrication between the piston ring-cylinder liner were studied and established two dimensional hydrodynamic lubrication models of the piston ring- cylinder liner. This model adopted the current authoritative theoretical results, such as average Reynolds equation, asperity contact model, Reynolds boundary conditions, viscosity-temperature and viscosity-pressure model. Using the finite element numerical method to solve the Reynolds equation, the paper obtained the minimum film thickness, friction and other lubricating characteristics parameters of piston ring- cylinder liner.2) This paper has completed static dynamic analysis of each component based on D’Alembert principle, the establishment of a 21-dimensional nonlinear mathematical models and numerical solution of equations using iterative methods. On the basis of the static dynamics and kinematics PGLM agency analysis, the paper obtained friction power of the deputy campaign of the PGLM bodies.3) Overall mechanical efficiency of the engine were studied, and analyzed some factors which were impact on the mechanical efficiency of the engine,such as the maximum explosion pressure, the output speed, quality, viscosity, coefficient of friction bushings, elastic force of piston rings and other factors. The results of the study showed that under certain conditions, the mechanical efficiency of the engine is up to 90%.The results also showed that the maximum explosion pressure, output speed and bushing friction coefficient have a significant impact on the overall mechanical efficiency, and variation could be explained and met with the actual situation.This paper studied the theoretical calculation of the rotary engine mechanical efficiency, and established a relatively complete calculation methods of the rotary engine mechanical efficiency. This calculation method could be applied to study the mechanical efficiency of a certain type of rotary engine, able to predict the mechanical efficiency of the rotary engine, and tell the effective way to improve its mechanical efficiency.