Intake Manifold Parametric Study to Optimize the Design for Acoustics using DFSS Approach

Noise pollution is a significant concern for global automotive industries which propels engineers to evolve new methods to meet passenger comfort and regulatory requirements. The primary 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 engine pulsations. This work proposes a Design for Six Sigma (DFSS) approach to optimize the intake manifold for better acoustic performance without compromising performance for a 3.6 L four-stroke engine for a 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. The intake manifold must be designed for better acoustics and engine performance, complicating the design process even more. The DFSS approach has input, output, control, and noise factors. Air-borne noise coming from the engine at different speeds is the input, and the throttle body noise is the output for the analysis. All the design parameters affecting the output are considered the control factors, and the two 3.6 L four-stroke engines with different valve timing are considered the noise factor since the design engineer does not control it. The experimental simulation setup will be based on the different levels of control factors. The simulation work for the throttle body noise was carried out using the GT-POWER software. The throttle body noise data (Sound pressure levels Versus Engine speed) was collected from 800 to 6400 rpm for rumble analysis. The design combination which minimizes the rumble was used as the final design.