Mahindra Two Wheelers used multiphysics simulation to meet engine noise regulatory necessities in its high-quit luxury motorcycles while retaining clients’ satisfaction.
Mahindra Two Wheelers builds a wide range of scooters and motorcycles for the Indian market. Thanks to the adoption of numerical simulation tools early in the development cycle, drivers and passengers can enjoy exquisite performance and mileage, together with a superior journey on hard Indian roads.
Mahindra used a multiphysics simulation to examine the NVH (noise, vibration, and harshness) performance of their bikes’ engine, intake, and exhaust structures.
The knowledge gained from numerical simulation studies enabled their engineers to improve their bike engines’ structural layout and acquire desired noise ranges. “COMSOL software program helped us to significantly lessen the number of layout iterations that we needed to go through, thereby saving time,” said Niket Bhatia, deputy manager of R&D, Mahindra.
There are numerous noise sources in an engine, along with the intake and combustion processes, pistons, gears, valve teach, and exhaust systems. Combustion noise is due to structural vibrations from a fast strain upward thrust inside the cylinders. These vibrations maintain from the powertrain to the engine casings through bearings, radiating noise.
Acoustics analysis entirely through bodily testing may be an expensive and time-eating technique. Mahindra’s crew determined to complement physical checking out with acoustics modeling to examine how the engine’s structure may inspire noise radiation. The research goal turned to finding the engine components that generate the maximum noise and provide you with modifications to the shape that might reduce it.
Using the COMSOL Multiphysics® software program, the researchers did an acoustic-radiation analysis of a single-cylinder internal combustion (IC) engine underneath the combustion load. The engineers enclosed the engine pores and skin in a computational area surrounded by a perfectly matched layer (PML). PMLs dampens the outgoing waves with minimal reflections (Figure 1). This allows for accurate results while reducing the dimensions of the computational domain.
The crew decided to recognize their analysis in the 800 Hz -2000 Hz frequency range, as physical experiments indicated that the bike’s engine noise radiation underneath the combustion load changed into dominant in that area of the acoustic spectrum. This desire allowed the crew to keep computational assets and recognize what regions radiate the most noise.
Based on this evaluation, the sound pressure level (SPL) was studied. Changes have been made to the cylinder head and block, including growing rib top and wall thickness and strengthening the mounting vicinity (Figure 2). By adjusting those parameters, a reduction in SPL was achieved at the focused frequency variety.