REDUCING ENGINE NOISE EFFECTS IN VEHICLE CABIN

Due to developing technology and customer expectations, car manufacturers are looking for new oppotunities to increase vehicle quality and performance. Research and development departments of car manufacturers are working on issues such as high fuel consumption, driving performance, dissemination of multimedia systems, driver assistance technologies and driving comfort. In recent years, the expectation of driving comfort by customers has become an important criterion for buying a car. One of the most important parementrs affecting driving comfort is NVH performance. Car manufacturers work to produce vehicles with more quieter cabinet in order to become more competitive in the growing sector. The most obvious voices complained by customers in cabin area; road noise, wind noise, tyre rolling noise, trim noise and engine noise. In this thesis, root causes of engine noise were determined and some corrective actions were taken in order to eliminate these root causes. In addition, how engine noise can be distinguished from other noise and how more quieter cabinet could be developed were discussed.