Intake Manifold Parametric study to optimize the design for Acoustics using DFSS Approach

Noise pollution is a major concern for global automotive industries which propels engineers to evolve new methods to meet passenger comfort and regulatory requirements. The main purpose of an intake manifold in an automotive vehicle is to allow the passage of clean air for combustion and reduce the noise generated due to the engine pulsations. The objective of this work is to propose a Design for Six Sigma (DFSS) approach followed to optimize the intake manifold for better acoustic performance without compromising on performance for a 3.6 L four stroke engine for Plug-in Hybrid electric vehicle (PHEV). Conventionally, intake manifold design has been an iterative process. It involves repetitive testing to arrive at an optimum design. Intake manifold must be designed for better acoustics performance and engine performance which complicates the design process even more. DFSS approach has an input, output, control factors and the noise factors. Air-borne Noise from engine at different speed is the input and the throttle body noise is the output for the analysis. All the design parameters which affect the output is considered as the control factors and the two 3.6 L four stroke engines with different valve timing are considered as the noise factor since it is not controlled by the design engineer. Commercial 1D simulation software GT-POWER® is used for this analysis. The simulation experimental set up will be made based on the different levels of control factors. The simulations work for the throttle body noise will be carried out in the GT-Power software. The throttle body noise data (Engine Speed (rpm) Vs Sound Pressure Levels (dBA)) will be collected and analyzed for rumble plot. The design combination which will minimize the rumble will be used as a final design.