In this work a multilevel Computational Fluid Dynamics (CFD) analysis has been applied for the design of a Formula race car exhaust muffler with improved characteristics of sound pressure level (SPL) and fluid dynamic response. The approaches developed and applied for the optimization process range from the 1D to fully 3D CFD simulation, exploring hybrid approaches based on the integration of a 1D model with 3D tools. Modern mufflers typically have a complex system of chambers and flow paths. There are a variety of sound damping and absorbing mechanisms working to quiet the sound flowing through a muffler and piping system. Two calculation methods were selected for this study. The muffler has a complex inner structure containing perforated pipe and fiber material. Computer-aided design (CAD) file of the muffler was established for developing Finite Element Analysis (FEA) model in AVL BOOST v2017 and another commercial advanced design software (SolidWorks 2017). FEA model was made to monitor the flow properties, pressure and velocity. After the model was verified, sensitivity studies of design parameters were performed to optimize the SPL of the muffler. The software analysis results are included in the paper. Recommendations are made for obtaining smoother SPL curves for various measurement methods.

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This paper explores the role of the computational fluid dynamics (CFD) modeling technique in the design, regulation, and production of the gasoline direct injection (GDI) engine combustion system through literature reviews. It begins with a brief analysis of injector technologies and the effect of spray characteristics on the optimization of the combustion system. The key challenges of optimizing a homogeneous-charge GDI combustion system are the enhancement of volumetric performance and homogeneity of fuel-air mixing with reduced wetting of surface fuel and the improvement of power output. Most of the calculations focused on dynamic mesh strategy to manage moving geometry varied from case to case. The techniques of the methods varied. During the opening event of a GDI gasoline-injector for automotive applications, the findings of the literature indicate the primary fuel atomization.

Literature review on flow acoustic methods and materials of an automotive muffler. a car is judged comfortable also depending on the acoustic level transmitted inside, and a thorough knowledge of acoustics of ducts and mufflers is needed for the design of efficient muffler configurations. Unstable exhaust gas at high temperature flowing from internal combustion engine manifold may cause of noise and vibrations conflicting with the high standard of acoustic comfort requested by this kind of vehicle. The basic gaols are to define most important methods to identify noise occur from the motion of fluid in case of turbulent model. Materials properties like velocity, temperature, thermal conductivity and density have been technical presented in this work.

Formula Student Car (FS) is an international race car design competition for students at universities of applied sciences and technical universities. The winning team is not the one that produces the fastest racing car, but the group that achieves the highest overall score in design, racing performance. The arrangement of internal components for example, predicting aerodynamics of the air intake system is crucial to optimizing car performance as speed changes. The air intake system consists of an inlet nozzle, throttle, restrictor, air box and cylinder suction pipes (runners). The paper deals with the use of CFD numerical simulations during the design and optimization of components. In this research article, two main steps are illustrated to develop carefully the design of the air box and match it with the suction pipe lengths to optimize torque over the entire range of operating speeds. Also the current intake system was assessed acoustically and simulated by means of 1-D gas dynamics using the software AVL-Boost. In this manner, before a new prototype intake manifold is built, the designer can save a substantial amount of time and resources. The results illustrate the improvement of simulation quality using the new models compared to the previous AVL-Boost models.The results illustrate the improvement of simulation quality using the new models compared to the previous AVL-Boost models.