Simulation Research On Intake System Of Gasoline Engine For Formula SAE

The Formula Racing Team of the Changsha University of Science and Technology(CRT)has participated in several FSAE events year by year.Seeking new breakthroughs has become the focus of research today.Because accelerating projects account for a higher proportion of total scores than fuel economy items in the competition,it is of great significance to improve the dynamics of the car for the team to improve the performance of the competition.The power of the racing car is largely influenced by the engine in the powertrain.The dynamic indicators of the engine include power and torque,all of which are closely related to the layout and size of the air intake system of the engine.The FSAE competition also stipulates that the intake limiter must be connected the throttle with the cylinder so as to limit the engine power,resulting in the mismatch between the rated power of the intake system of the original engine and the rated power.Therefore,it is very important to study the simulation of air intake system.This article focuses on the multi-dimensional simulation of the intake system of the HONDA CBR600RR racing gasoline engine.Firstly,on the basis of fully researching related literatures at home and abroad,the status quo of engine intake flow simulation research is introduced,and the dynamic effect of intake system is studied.Combined with the actual conditions of the engine,based on the dynamic effects of the intake system,a reasonable matching scheme for the intake manifold and the regulated resonant cavity is proposed.Then,the one-dimensional model of the CBR600RR engine was established in the professional engine simulation software GT-Power.After basic verification of the model and the bench test,the effects of different intake manifold geometry sizes and cavity volume changes on engine power,torque,and aeration efficiency were analyzed.Based on the data obtained from the one-dimensional simulation software,a three-dimensional model of the air intake system including an air filter,an air intake limiter,a throttle valve,a resonant cavity,and an intake manifold was established through UG software,and the CFD was performed pre-treatment.Then it was imported into the Fluent module of the three-dimensional simulation software ANSYS.The restrictive valve and the resonant cavity were simulated and compared respectively,and the differences in parameters such as velocity field,pressure field,and flow rate under different structural dimensions were compared.In this paper,the one-dimensional simulation of the engine working process and the three-dimensional CFD flow field analysis are combined,and the influence of the structural parameters of the intake system on the intake performance is theoretically studied,which helps to demonstrate the internal fluid flow effect of the intake system.Finally,the geometry of the restrictor valve was determined,the intake manifold length was increased to 300mm,the cavity volume was expanded to 3.0L,and the total outlet flow reached 0.135kg/s,making the intake effect 12.5%higher than before.This improves the engine's dynamic performance and provides theoretical support for the design of the FSAE racing engine intake system.