As a crucial component protecting the vehicle body from mud and sand, the fender's structural design directly impacts wind noise during driving. Optimizing the fender structure to reduce wind noise requires a systematic design approach, drawing on aerodynamic principles and incorporating materials science and structural mechanics to achieve a balance between wind noise and protective performance.
Wind noise from the fender primarily stems from airflow interference between it and the vehicle body and tires. At high speeds, airflow creates turbulence on the fender surface, generating vortex shedding and resulting in air vibration and noise. Furthermore, improperly designed gaps between the fender and tires can create high-pressure zones within the wheel arches, exacerbating wind noise. Therefore, structural optimization should focus on reducing airflow separation, smoothing airflow paths, and reducing vortex intensity.
Streamlined shape design is a core method for reducing wind noise. Traditional fenders often employ planar or simple curved structures, which can lead to premature airflow separation. By incorporating biomimetic design principles, such as mimicking the curved shape of bird wings, airflow can better conform to the fender surface, delaying the separation point and reducing vortex generation. Meanwhile, the fender edges should be rounded to avoid sharp corners causing abrupt airflow changes and further reducing turbulence intensity.
Surface smoothness optimization is crucial for reducing wind noise. Rough surfaces exacerbate airflow friction, increasing energy loss and noise. Using high-precision molds to manufacture the fender ensures surface flatness, and a dense coating is formed through spraying or electroplating processes, significantly reducing airflow resistance. Furthermore, some high-end models employ active aerodynamics designs, such as adjustable deflectors, which automatically adjust the fender angle according to vehicle speed, achieving dynamic airflow optimization and further suppressing wind noise.
Structural topology optimization technology provides a new approach to fender lightweighting and wind noise reduction. Through finite element analysis (FEA) and computational fluid dynamics (CFD) simulations, the stress distribution and airflow characteristics of the fender under stress can be accurately identified. Based on topology optimization algorithms, redundant materials can be removed while maintaining structural strength, forming hollow or lattice structures. This design not only reduces weight and the burden on the suspension system but also reduces airflow interference by decreasing the exposed surface area of materials, achieving dual optimization of wind noise and energy consumption.
The way the fender connects to the body also affects wind noise performance. Traditional rigid connections easily lead to vibration transmission and resonance noise. Using flexible connectors, such as rubber bushings or hydraulic supports, can effectively isolate vibrations and reduce noise transmission paths. Simultaneously, optimizing the connection point location to prevent airflow vortices at the connection point can further reduce wind noise. For example, placing the connection point on the inside of the fender utilizes the body structure to shield the airflow and reduce direct impact.
Multi-component collaborative design is key to improving overall aerodynamic performance. The fender needs to form an integrated airflow guidance system with components such as wheel arches and side skirts to ensure a smooth transition of airflow under the body. By simulating the airflow interaction between different components, the gap size between the fender and the wheel arches can be optimized to prevent the formation of high-pressure zones within the gap. Furthermore, some models use a closed wheel arch design, completely enclosing the tires, eliminating airflow interference at its source and achieving ultimate quietness.
Material innovation provides more possibilities for fender wind noise optimization. Lightweight, high-strength materials, such as carbon fiber composites or aluminum alloys, can reduce weight and lower airflow drag while maintaining structural strength. Furthermore, the application of novel porous materials or sound-absorbing coatings can further reduce noise generation by absorbing or dissipating airflow energy. For example, laying porous foam material in the inner layer of the fender can effectively absorb airflow vibrations and reduce wind noise propagation.
