Modeling method of one-dimensional CFD simulation analysis model of automobile intake and exhaust system

Abstract

The invention discloses a modeling method for a one-dimensional CFD simulation analysis model of an automobile intake and exhaust system, and the method comprises the following steps: S1, building a finite element model of the intake and exhaust system, and the finite element model does not comprise parts irrelevant to gas flow; s2, extracting a pipeline closed surface in the finite element model, performing grid processing on the pipeline closed surface, extracting a shell closed surface in the finite element model, performing grid processing on the shell closed surface, and exporting the pipeline closed surface and the shell closed surface as a geometric model file in an STL format; s3, importing the geometric model files of the pipeline closed surface and the shell closed surface into GT software, and converting the pipeline closed surface and the shell closed surface into a pipeline solid model and a shell solid model by adopting a GEM-3D tool of the GT software; and S4, supplementing parts irrelevant to gas flow into the pipeline and shell solid models, establishing a three-dimensional solid model of the intake and exhaust system, and performing discrete treatment to obtain a one-dimensional CFD simulation analysis model of the intake and exhaust system. The method can ensure the modeling precision and improve the modeling efficiency.

Description

technical field [0001] The invention relates to an automobile intake and exhaust system, in particular to a modeling method for a one-dimensional CFD simulation analysis model of the automobile intake and exhaust system. Background technique [0002] GT-SUITE is a multi-physics simulation analysis software platform developed by Gamma Technologies. As a vehicle and internal combustion engine performance simulation analysis platform, it has been widely used in the automotive and internal combustion engine industries. GT-Power, the engine thermodynamic performance simulation analysis software, is mainly used in Simulation analysis of internal combustion engine power, economy and intake and exhaust noise. [0003] In order to accurately simulate the power, economy and intake and exhaust noise of the engine, it is necessary to establish a high-quality engine one-dimensional performance model that retains sufficient intake and exhaust gas path geometric features. GT-SUITE provide...

AI Technical Summary

Problems solved by technology

According to the user manual and case tutorial of the software, the simple gas path model (the basic components of the gas path have no overlap in the flow direction and are only sequentially connected) can easily complete the conversion from three-dimensional to one-dimensional, but for more complex In terms of the system such as the automobile exhaust system including the muffler (the basic components of the gas path overlap in the flow direction, such as the pipeline inside the muffler), the case provided by GT-SUITE software is in GEM-3D According to the geometric parameters of the exhaust system, the corresponding components are established one by one, that is, GEM-3D is used as a CAD tool to establish a three-dimensional solid model of the gas path. There are many parameters to be collected, and because of the 3D modeling capabilities provided by GEM-3D It is quite basic, so it takes an engineer 3-5 working days to build a complete intake and exhaust system model in this way, which is obviously not efficient, and does not make full use of the 3D CAD digital model completed by the design engineer

In addition, if you directly use the basic component template modeling in GT-Power without GEM-3D software, you will lose a lot of geometric features of the intake and exhaust system, and you cannot get a system model with sufficient accuracy

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