Impact of Rotor Balancing on Noise and Vibration Levels in Automotive Fuel Supply Modules

Rotor balancing is essential for minimizing vibration and noise in industrial and automotive applications. With increasing consumer demand for quieter vehicle interiors, automotive components are now subject to stricter noise and vibration standards. This study investigates the noise generated by fuel supply modules, which play a critical role in delivering pressurized fuel to engines while maintaining low noise levels. An overview of rotor balancing standards is presented, followed by an analysis of how varying degrees of unbalance influence the vibration and noise characteristics of fuel supply modules. To achieve this, rotors were assembled on electric pump samples with defined upper and lower limits of unbalance and conducted tests at the Robert Bosch Ltda laboratory. Utilizing frequency domain analysis, we examined the vibration and noise signals to identify fundamental and harmonic frequencies, thereby assessing the impact of unbalance on overall performance. Measurements were taken at both the electric fuel pump and the fuel supply module levels, reflecting realistic operational conditions. The results demonstrate a significant correlation between rotor unbalance and the resultant noise levels in the assembled product, specifically, as the degree of unbalance increases, so does the noise level. These findings highlight the necessity for designers to consider rotor unbalance during product development, ensuring that noise requirements are met while balancing production costs. This research contributes to the ongoing efforts to enhance the acoustic performance of automotive components, aligning with consumer expectations for quieter vehicles.