Ten years ago, NVH performance was primarily a passenger car concern in India. Buyers of trucks, buses, and light commercial vehicles were focused on payload capacity, fuel economy, and reliability. Cabin comfort in terms of noise and vibration was a secondary consideration, particularly in the value-oriented segments that dominate Indian commercial vehicle volumes.
This has changed. Several factors have converged to push NVH up the commercial vehicle priority list in India. Driver welfare regulations and awareness have increased, particularly in long-haul trucking, where occupational health concerns around whole-body vibration and noise-induced hearing issues are receiving more attention. Fleet operator premiumization has driven demand for higher-quality cabins in upper-segment trucks. And Indian OEMs exporting to international markets, particularly in Southeast Asia, Africa, and the Middle East, face customer expectations that are set by Japanese and European competitive benchmarks where NVH performance is more established as a buying criterion.
The challenge for Indian commercial vehicle OEMs and their Tier-1 suppliers is that NVH development done purely through physical road testing is slow, expensive, and provides limited diagnostic insight. You know the vehicle is too noisy. You do not always know precisely why or where the energy is coming from. Simulation changes both of these things.
NVH simulation encompasses several analysis types that together build a picture of how vibration and acoustic energy move through a vehicle structure. Structural finite element analysis identifies how the body-in-white or chassis structure responds to excitation from the powertrain and road. Transfer path analysis traces the path that vibration energy takes from its source to the driver’s seat or the cab interior. Acoustic cavity analysis models how sound pressure builds up inside the cabin. And powertrain excitation modeling captures the vibration forces generated by the engine and driveline that are the primary inputs to the system.
Simcenter from Siemens covers all of these domains within a connected environment. The advantage of a connected environment is that when a design change is made, its effect can be evaluated across all the relevant analysis types without rebuilding separate models in separate tools.
One of the more important aspects of Simcenter for Indian commercial vehicle development is its test-simulation correlation capability. A structural simulation model of a cab or chassis structure is only useful for design decisions if its predictions are validated against measured physical test data. Simcenter provides tools for comparing simulation predictions with accelerometer and microphone measurements from physical tests and for updating the model to improve correlation.
Once a model is correlated, it can be used to predict the NVH effect of design changes with confidence. This is where the time and cost savings come from. Instead of building and road testing three or four physical variants to determine which stiffener configuration reduces cab boom frequency, you run the comparison in simulation, select the best candidate, and build one physical prototype for final validation.
At the OEM level, Tata Motors and Ashok Leyland have established NVH simulation teams and use simulation as part of their development processes. The capability gap is more pronounced at the Tier-1 level, where suppliers of cab structures, frame members, and suspension components are often asked to provide NVH performance guarantees for their subsystem without having the simulation capability to validate those guarantees internally.
For Tier-1 suppliers in this position, building NVH simulation capability is increasingly a commercial necessity rather than a technical aspiration. The OEMs that are investing in NVH competitiveness will progressively expect their supply base to contribute to the effort rather than requiring all the analysis to be done at the OEM’s expense.
