Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Winter 8th Sem 2180214 Noise, Vibration And Harshness And Safety Previous Question Paper
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE- SEMESTER?VIII (NEW) EXAMINATION ? WINTER 2020
Subject Code: 2180214 Date: 21/01/2021
Subject Name: Noise, Vibration & Harshness And Safety
Time: 02:00 PM TO 04:00 PM Total Marks: 56
Instructions:
1. Attempt any FOUR questions out of EIGHT questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) Define Noise, vibration and Harshness.
03
(b) Explain shortly for Human ear anatomy with mechanism of hearing.
04
(c) Note down various vibratory systems into the vehicle, Also discuss the study 07
principle of Raw, Pitch and Yaw for velocity and movement.
Q.2 (a) Classify Mechanical vibrations. Also discuss the Damped and Un-damped 03
vibration.
(b) Explain the terms: 1] Degree of freedom 2]Periodic motion 3]Time period 04
4] Simple Harmonic Motion
(c) Discuss the harmful effects of vibration and noises from the vehicular body. 07
Also explain its reduction and eliminating methods in detail.
Q.3 (a) Write a short note on psychological effects of noise on human.
03
(b) List the factors affecting on Piston Slap noise? Also write the counter 04
measures for it.
(c) Explain Anechoic chamber with sketch for the measurement of vehicle 07
noise.
Q.4 (a) Explain sound waves and its propagation?
03
(b) What are the differences between Structure borne and air borne noise.
04
(c) Explain Bearing noise, Cam system noise and Timing chain noise from the 07
automotive.
Q.5 (a) List the various methods to minimize the Vibration and Noise in vehicle.
03
(b) Explain in brief Mechanical type vibration exciter with the help of sketch.
04
(c) Explain Squeak, Rattle and Buzz noise with its frequency range. Also 07
discuss the noise generating points and reduction methods in vehicle.
Q.6 (a) List the various vibration analysis softwares in brief.
03
(b) Brief about Passenger seats and steering wheel vibration with the sketch.
04
(c) Discuss Vibrations and Noise in vehicle driveline system. Also write for the 07
terms shuffle, clunk, driveline boom and axle whine.
Q.7 (a) List the various NVH-legislations applicable for vehicles across the India.
03
(b) Explain "Pass-by Noise" method with the help of sketch.
04
(c) Draw and Explain vibration transfer path from vehicle suspension system to 07
the other included systems of vehicle.
1
Q.8 (a) What does it mean by "Churning effect" in automobile transmission systems 03
and relate it with vibration phenomena.
(b) What do you understand about vibration exciters? How does it work? 04
Explain working principle of Electrodynamics exciters.
(c) What does it mean by Air pumping noise? From where it is can be 07
generated? What is the significance of tyre tread pattern on air-pumping
noise?
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This post was last modified on 04 March 2021