Feasibility verification of reducing the total sound pressure level of multiple cooling fans for fuel cell vehicle

The high-power operation or generation in fuel cell vehicle (FCV) generates massive heat in the powertrain. Multiple cooling fans are used to ensure the heat dissipation requirement, causing severe fan noise problems. This study aims to analyze the noise characteristics of multiple cooling fans. Hence, the feasibility of reducing the total sound pressure level is verified by cooling fan control strategy. A numerical calculation model of multiple cooling fans is established for the entire vehicle’s internal and external sound fields. Then, this numerical calculation model is verified using experiments. The contribution of multiple cooling fans to the total noise in FCV is analyzed under the same duty cycle of fan. The selection method of cooling fan control strategy is proposed, and the feasibility of reducing noise is verified under three different working conditions. In parking charging working conditions, the total sound pressure level near the driver’s ear decreases by 0.6, 1.9, and 2.8 dBA, respectively. In idling conditions, the total sound pressure level near the driver’s ear decreases by 0.4, 1.6, and 2.4 dBA, respectively. In constant speed working conditions, the total sound pressure level near the driver’s ear decreases by 0.6, 2.2, and 3.1 dBA, respectively.