Analysis the Influence of Pressure Distribution on Exhaust Manifold Using FEM

Abstract

In this paper the 3D model of the exhaust manifold was realized using Autodesk Inventor Professional 2024 and finite element analysis was performed, in order to determine the state of stress and deformation, by applying restrictions and loads conditions. The materials chosen, for exhaust manifold, was in accordance with the specialized literature. The materials taken for static analysis was Stainless Steel 440C and Iron Gray Cast. Following the comparative study for the two models, it can be specified that the importance of the material for the construction of the exhaust manifold depends on the mass properties and their design.

Introduction

I. INTRODUCTION

The exhaust manifold is the first part of the vehicle's exhaust system, it connects to the engine and records the emissions of the engine in operation. The exhaust manifold receives the air-fuel mixture from several cylinders of the vehicle's engine. The exhaust manifold receives all of the engine's burned gases, but also uses very high temperatures to completely burn the unused or incompletely burned gas. The distributor has the first oxygen sensor in the exhaust system to check the amount of oxygen entering the system. The oxygen sensor monitors the amount of oxygen and tells the fuel injection system to increase or decrease the amount of oxygen in the mixture used to feed the engine. Basically, the exhaust manifold acts as a funnel and is used to collect all the engine emissions. When they are in one place and burned completely, the collector directs the emissions to the rest of the exhaust system [1].

The principle of the exhaust manifold explains that it is designed to avoid overlapping exhaust strokes as much as possible, thus keeping back pressure to a minimum. This is often done by splitting the exhaust manifold into two or more branches so that two cylinders not to burn out in the same branch at the same time [2].

The pressure inside the gallery is between 100 kPa and 500 kPa and the temperature is used to exhaust the collector, which will lead to thermo-mechanical failure [3]. Back pressure is created due to the exhaust system not being completely released before the gases from the other cylinder are released. These gas pressure waves restrict the engine's true performance possibilities. The modelling strategy developed in many studies consists in separated thermal and mechanical simulations, performed using the Finite Element Analysis.

V. Hugar [4] presents an analysis to investigate stresses for different scenarios when Structural Steel and Aluminium Alloy materials was used for exhaust manifold and he utilized ABAQUS software for the Finite Element Analysis. The results suggest the suitable material for the manifold is Structural Steel.

II. EXHAUST MANIFOLD DESIGN

Solid modelling of the exhaust manifold was done using Autodesk Inventor, version 2023 with the literature data and the solid model of the exhaust manifold are shown in Fig. 1.

Conclusion

The scope of this paper was to carry out a study of the behavior under the action of pressure of a exhaust gallery. In order to determine the state of stresses and deformations, the 3D models of the exhaust gallery were made with the help of the Autodesk Inventor Professional 2024. After running the static analysis, the maximum values of the Von Mises stress were recorded for Stainless Steel 440 C exhaust gallery when a pressure of 500 kPa was applied and the maximum values of the deformations it was obtained for Iron Gray Cast at the same pressure. Following the comparative study for the models, it can be specified that the importance of the material for the construction of the exhaust gallery depends on the mass properties and their design. The study can be continued with a more complex analysis by using other materials under the same stress conditions and by studying thermal analysis of the exhaust gallery.

References

[1] L. Hung-Hsiao, C. Chin-Hsien, H. Kan Lin, “Modeling and design of air-side manifolds and measurement on an industrial 5-kW hydrogen fuel cell stack” International Journal of Hydrogen Energy 42(30), DOI: 10.1016/j.ijhydene.2017.06.057, June 2017. [2] C. Delpretea. “Multiaxial damage assessment and life estimation: application to an automotive exhaust manifold”, Proceeding: 2 (2010) 725–734). [3] C. Rita, “Structural and Thermal Analysis of an Exhaust Manifold of A Multi Cylinder Engine”, International Journal of Engineering Research & Technology (IJERT), ISSN: 2278-0181, Published by, www.ijert.org NCETEMS-2015 Conference Proceedings. [4] V. Hugar, et al., “Analysis for Exhaust Manifold of an Off-Road Vehicle Diesel Engine-FEM Approach” Journal of Xidian University, ISSN No: 1001-2400, Volume 13, Issue 6, June 2019. [5] D Sunny Manohar, J Krishnaraj, “Modeling and Analysis of Exhaust Manifold using CFD”, IOP Conf. Series: Materials Science and Engineering 455 (2018) 012132, doi:10.1088/1757-899X/455/1/012132. [6] Rita, “Structural and Thermal Analysis of an Exhaust Manifold of A Multi Cylinder Engine”, International Journal of Engineering Research & Technology (IJERT) ,ISSN: 2278-0181, NCETEMS-2015 Conference Proceedings, 2015.

Copyright

Copyright © 2023 Valentin Mereuta. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.