What does NVH mean?
4 Answers
NVH is the English abbreviation for Noise, Vibration, and Harshness. Below is relevant information about automotive NVH: The role of NVH: NVH is a comprehensive issue that measures the manufacturing quality of automobiles, providing the most direct and superficial experience for car users. NVH issues in vehicles are one of the concerns for major automotive manufacturers and component companies in the international automotive industry. Internal relationships of NVH: The generation of automotive vibration and noise is not independent but closely interrelated. It can be said that noise originates from vibration, and these three factors—vibration, noise, and comfort—are closely connected. It is necessary to reduce vibration and noise while improving ride comfort, ensuring product safety, environmental friendliness, and performance. Characteristics of NVH issues: NVH issues are systemic. For example, if a car's cabin noise is loud while driving, and the source is traced back to the engine, this noise problem may involve three aspects: first, the engine itself is noisy; second, the vibration damping effect of the engine mounting components is poor; and third, the sound insulation technology of the cabin front wall and floor is inadequate.
I pay special attention to comfort issues in the driving experience, and NVH refers to the control of noise, vibration, and harshness in vehicles. For example, the rumbling sound of tires while driving, the buzzing of the engine during acceleration, and even details like aging door seals causing wind leaks all fall within the scope of NVH improvements. The new car I recently test-drove used hydraulic bushing suspension technology, and surprisingly, there was no numbness in the steering wheel when going over speed bumps—this is the effect of optimizing vibration transmission. Remember to check the engine mounts every 20,000 kilometers, as aging rubber can significantly increase vibration problems.
Friends who are into car modifications are all familiar with NVH (Noise, Vibration, and Harshness), as we mainly focus on addressing various noises inside the cabin. Last time when I added soundproofing materials to my car, I discovered that different materials can target specific noise reductions: sandwich composite materials applied behind the dashboard block engine noise, while butyl rubber in the wheel arches prevents tire noise. After applying vibration damping sheets to the door panels, knocking on them produces a solid 'thud' instead of a 'clang.' This way, even when driving at 60 km/h, you can clearly hear the music after lowering the volume by two notches. It's recommended to use a decibel meter during modifications to test and prioritize noise sources exceeding 35 decibels.
After ten years in auto repair, I've encountered numerous NVH complaint cases. The three most common rattles are: the dripping sound from the roof on rainy days caused by blocked drainage pipes; the clunking noise from the trunk on bumpy roads due to unsecured tools; and the creaking sound from the dashboard in winter stemming from plastic parts' thermal expansion and contraction. These can actually be improved at low cost, such as applying grease to glove box rails or wrapping seatbelt buckles with velvet tape. Remember not to blindly stuff soundproofing cotton for rattles - precisely identify the resonance point instead.
