Study On LJ465Q Variable Length Intake Manifold

Engine intake system is one of the important parts of the engine, it affects theengine’s volume efficiency and the uniformity of air entering to each cylinder directly,so as to make the engine get better performance, and has a great influence on theservice life of the engine. Wherein the intake manifold is the important part of theintake system, has great significance value to research.When the engine is working, because the intake valve, piston or the other parts ofthe engine are moving with regularly and intermittently, so make a phenomenon thatthe dynamic effects of the intake manifold system in the intake system. Thevariable-length intake manifold is able to use this phenomenon, shorter intakemanifold equipped in the high speed zone, and a longer intake manifold at a moderatespeed zone, to improve the engine’s volume efficiency and increase the air mass foldinto the cylinder, so as to make a batter performance of the engine.Firstly, this study use the GT-POWER software to establish LJ465Q workingprocess model,and compared with experimental data to verified the model reliability.Secondly use the model to analysis the impact of the engine performance (volumeefficiency, power,torque and the best fuel rate) of different length intake manifold.Finally, through the analysis, not only obtained the variable length range of theintake manifold and the control strategy, but also proposed a new kind ofvariable-length intake manifold structure.In order to modeling the3D variable-length intake manifold structure, so must beanalyzed based on the intake manifold engine one-dimensional numerical, and thenuse Fluent software for the three-dimensional numerical analysis, to optimize intakemanifold shape of the structure, and to reduce the air flow resistance and flow energylosses.Analysis result showed, improved intake manifold is batter than before. Inaddition, analysis the pressure uniformity and mass flow uniformity in the intakemanifold when the engine is working. The analysis results show that there is litterdiffers between each intake manifold,which have a satisfactory results. Finally, usethe3D design software UG to model design the variable-length intake manifold.This paper presents a new kind of variable-length intake manifold structure,andcombine the computer-aided design and analysis to complete the variable-lengthintake manifold design work, and make the engine have a certain upgrade,It has acertain significance reference value in the research and design of variable-lengthintake manifold.