The Design And Experimental Research On Atkinson Cycle Gasoline Engine Converted From Otto Cycle

Due to the traditional Otto cycle engine using the throttle to control load, fuel consumption was high and thermal efficiency was low, that cannot meet the demand of hybrid electric vehicles. At present the Atkinson cycle engines are widely accepted in hybrid vehicles, with high inflation rate, inlet valves later closing to control load characteristics, so the thermal efficiency and fuel consumption on the Atkinson cycle engine has unique advantages, therefore, studying on the Otto cycle engine improved design for the Atkinson cycle was necessary.This paper studied on an Otto cycle engine improvement design for the Atkinson cycle engine by combining the methods of numerical simulation and experimental verification, and analyzed on the performance of the Atkinson cycle engine, its main work and innovative points are as follows:(1)In the one dimensional simulation software GT-POWER, the Otto cycle engine simulation model was established,through software simulated,the simulation results were compared with the test results,the error was within 5%,so the simulation model was accurate.(2)The different compression ratio, inlet CAM work Angle and inlet valve closing time were analyzed from the indicated thermal efficiency, pumping gas loss and fuel consumption rate by simulation calculation, the best compression ratio and inlet CAM work angle were chosen, redesign for the key parts based on the best improvement program, the Atkinson cycle engine design and development was completed.(3)The performance of Atkinson cycle engine and the original machine were analyzed,from the external characteristic、typical working condition and universal characteristics according to the results of the experimental bench calibration,the experimental data showed that the machine minimum fuel consumption rate reduced to 230g/(k W·h),then the experimental results were compared with the simulation calculation results to verify the rationality of the design of the simulation.