Sketch a graph of the microphone signal, Mathematics

Figure shows noise results for a prototype van measured on a rolling road. The vehicle had a four-cylinder-in-line engine. The engine speed was varied in 3rd gear from just above stall to about 4500 rpm. The sound pressure at a representative interior position was measured in dB using the standard reference, namely 20 ?Pa. Figure Q2 shows the overall noise level and also the component associated with the second harmonic of the engine speed.

a) The noise peak at 3600 rpm is due to an acoustic resonance with a standing wave between the floor and roof of the van. What is the frequency of this resonance and what is the vertical dimension of the van interior?

b) Sketch a graph of the microphone signal at 3600 rpm. Your graph should include time and sound pressure axes with scales to show the ranges for the signal you have sketched.

c) Comment on the overall results in Figure Q2 indicating if they are acceptable or if they indicate a specific NVH problem.

d) It would have been better to have measured the sound pressure in dBA. Explain why.

768_engine speed.png

Posted Date: 3/25/2013 1:19:15 AM | Location : United States







Related Discussions:- Sketch a graph of the microphone signal, Assignment Help, Ask Question on Sketch a graph of the microphone signal, Get Answer, Expert's Help, Sketch a graph of the microphone signal Discussions

Write discussion on Sketch a graph of the microphone signal
Your posts are moderated
Related Questions
Example of 3-D Coordinate System Example: Graph x = 3 in R, R 2 and R 3 .   Solution In R we consist of a single coordinate system and thus x=3 is a point in a 1-D co

Explain Basic Concepts of Parallel Lines ? Parallel lines are defined in section 1.2 and we use "//" to denote it. From the definition, we can get the following two consequenc

Explain Adding Rational Expressions with Different Denominators When you add or subtract fractions or rational expressions that have different denominators, you must first find

Find out all intervals where the given function is increasing or decreasing. f ( x ) = - x 5 + 5/2 x 4 + 40/3 x 3 + 5 Solution To find out if the function is increasi

Circles In this section we are going to take a rapid look at circles.  Though, prior to we do that we have to give a quick formula that expectantly you'll recall seeing at som

Assumptions and Application of T Distribution Assumptions of t distribution 1. The sample observations are random 2. Samples are drawn from general distribution 3.

A pipe has a diameter of 2.5 inches. Insulation which is 0.5 inches thick is placed around the pipe. What is the diameter of the pipe along with the insulation around it? The i

It takes light 5.3 × 10 -6 seconds to travel one mile. What is this time in standard notation? In order to convert this number to standard notation, multiply 5.3 through the f


Laws of Set Algebra From the given Venn diagram where T is the universal set and A its subset that we can deduce a number of laws as: i. A υ Ø = A ii. A υ T = T