National Conference on Emerging Trends of Research in Applied Sciences,

Experimental & Computational Techniques

Organized By: Jodhpur institute Of Engineering & Technology

Changing Vehicle Class Using Acoustical Engineering

Presented By:Ravina Dadhich

Inside This Presentation

IntroductionWhat is Acoustic?Why we need to reduce Acoustic?How to handle Acoustic Problems?Damping MaterialsSound AbsorbersConclusion

Introduction

Over last few years we have seen diversified advancements in automobile industry which helps out in increasing the vehicle’s class by providing extraordinary comfort to passengers. To provide better comfort the acoustic performance is gaining a very much importance. In order to fulfil the high customer expectations the industry designers are spending a large amount of money to control the noise ,heat and vibration problems in passenger cabin.

This reduction of noise can be achieved with the combined effort of both acoustical and automobile engineers.

What is Acoustic?

Acoustic is branch of physics that deals with problems related to noise.

Why We Need to Reduce Acoustic?

• It reduces the vehicle’s efficiency.• It directly affects the atmospheric noise.• Causes irritation in passenger cabin.• To as to give high customer satisfaction.

How to Reduced Acoustic Problems

The combined efforts of industry engineer give rise several methods out of which two main are discussed here:

1) Use of Damping Materials

2) Installation of Sound Absorbers

Damping Materials

Damping is a physical term that refers to the changing of energy.

It takes energy from sound waves and converts it into a silent energy.

They acts as a shock absorber for sound waves.They are installed in the doors, in the roof,

under the carpet and behind the rear seat and fire wall.

Types of Damping Material

1. Formable Floor Barrier Material:-

They are used to at irregular areas of floor plane.

They are light-weighted.

They contain neoprene material which also helps in controlling the vibration problems.

2. Moldable Road Noise Barrier:- They are used to control the low frequency road noise.

They are installed near wheel arches.

It contains the neoprene layer which creates the ‘air spring’ which prevents the sound energy from passing through the dense layer.

3) Flexible Floor Barrier: They are loaded with vinyl bass material. They are installed on the floor base of

passenger cabin. They are light-weighted.

3)Flexible Road Noise Barrier: They are used to control high frequency noise. It consists mainly of neoprene material but a small

fraction of vinyl material gives it a great benefit and it is most preferred damping material.

They are installed on flat areas of the floor pan.

Sound-absorbing materials absorb most of the sound energy.They are used in a variety of locations and have been used increasingly in the construction of automobiles because of their low weightSome of the best materials are discussed below which fits best in handling automobile acoustic.

Sound Absorbers

Sound Absorbing Materials

1) Porous Asphalt: They are used in passenger cabin.They not only used to reduce tire/road noise

but and reduce the splash up behind vehicles during heavy rainfall.

2) Smart Absorbing Materials The absorber is made of melamine foam

(made of melamine resin, a thermo set polymer).

The main advantage of material is that it is lightweight, thin, efficient which gives out promising results.

Conclusion

Sound and vibration parameters must be considered as important elements regarding comfort and perceived quality. These two parameters are one of the important aspects for providing higher customer satisfaction. In this presentation two most commonly used techniques are discussed. These new advancement in ongoing methods are helpful in handling acoustic problems due to low frequencies. There is a need for an innovative high- performance measurement technology to meet increasing requirements with respect to increasing customer expectations and shortened development cycles.

Thank you!