High-speed Motorcycle Gasoline Engine Performance Simulation And Optimization Research

With more and more people owning Vehicles in China,the urban traffic congestion has been becoming a serious problem.Through scientific road management and planning,motorcycle which occupies less space to drive and park can solve this phenomenon of the traffic jam to a large extent.At the same time,due to energy crisis and environmental pollution,we need higher performance motorcycle engines.In this paper,a single-cylinder gasoline engine for motorcycle was taken as the research object.The results of numerical simulation and experiment were compared to optimize the compression ratio,the structure of intake and exhaust system,cam profiles and airflow in cylinder and so on,at the same time,matching the engine mixture concentration and ignition timing,to achieve the purpose of improve engine performance and fuel economy.Analyzed on the performance of the modified engine and verify the simulation project.The main research content of this article is as follows:(1)In the One dimensional simulation software GT-POWER,the original engine simulation was established,the engine's performance was compared through the original engine experimental results and the results of the simulation,we will control the error within 5%,so the simulation model was correct.(2)The engine compression ratio,intake and exhaust system and valve train were analyzed and calculated to find the influence rule of these parameters on engine performance by simulation calculation.Conclude the influence rule and complete the engine performance optimization under these guidance,and results show that the compression ratio can rise up to 10.5.After optimization intake and exhaust system,dynamic performance of the intermediate and high speed got a big improvement,especially torque improvement under medium speed,greatly improve the acceleration of the engine.Redesign the intake and exhaust CAM profile and change the working angle and valve phase based on Timing-Drive,the performance of low and high speed are improved significantly.In terms of organization combustion,the combustion chamber structure were designed and improved,and make full use of the flow of gas,combined with matching and adjustment the mixture concentration and the ignition advance angle,engine performance was further improved.(3)The performance of improved engine and original engine were compared from the external characteristic.universal characteristic and typical working conditions according to the result of the experimental bench.The results show that the dynamic performance of engine has been improved considerably.The maximum power reaches 10.04 kW(8500r/min)and improved by 9.80%compared to the original engine;The maximum torque reaches 14.16 N·m(6000r/min)and improved by 8.48%;The minimum fuel consumption rate reduced to 259.48 g/kW·h(3500r/min)and reduced by 3.86%,the performance parameters of the improved engine meet the requirement of manufacturer.