Solution to Homework 4
Acoustics I
2007
The figure shown below shows a typical sound power measurement setup in semianechoic chamber (all five surfaces of the room are anechoic, while the floor is rigid. In the figure, Q above the rigid surface is the act
Homework 1 Due date: 1014106
Acoustics I
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A S DOF system is operating on a foundation defined by impedance Plot the displacement amplitude
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Acoustics I
HW 2
Fall Qt. 2006
Due Date: 10/16
Problem1: In a manufacturing plant, SPL is measured 90 dB when 20 identical machines that generate relatively steadystate, broadband noise are operating. The background noise level is measured 70 dB when no
Acoustics J
HW2
Fall Qt. 2006
Due Date: 10116
P robleml: In a manufacturing plant, SPL is measured 90 dB when 20 identical machines that generate relatively steadystate. broadband noise are operating. The background noise level is measured 70 dB when no
HW 3
Acoustics I
Fall 2006
Due: October 30
Problem 1 Derive the acoustic impedance Za of the Helmholz resonator. Now this resonator is used as a side branch as shown in the figure. Derive the expression for T in terms of given parameters. Plot TL = 10 log
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Homework 4
Acoustics I 2006, Fall Qt.
Due date 11/15, 2006
Problem 1 We want a design analysis for a reactive type muffler to be used for a small automobile. The firstcut model is shown below. Using the 4 pole approach: 200oC, 1 atm d=5 cm Engine side D=
Solution to Homework 4 Acoustics I 2006, Fall Qt. Problem 1 We want a design analysis for a reactive type muffler to be used for a small automobile. The firstcut model is shown below. Using the 4 pole approach: 200oC, 1 atm d=5 cm Engine side D=15 cm d=5
Homework 1
Acoustics I
Fall 2007
Due date: October 3, 2007 A SDOF system shown in the figure below is operating on a foundation of impedance Z F defined by % 27, 000 1.875 106 270 106 Z F = j 3000 , j 3000 , or 3000 . Plot the % displacement amplitude X 1
Homework 1_Solution
Acoustics I
Fall 2007
A SDOF system shown in the figure below is operating on a foundation of impedance Z F defined by % 27, 000 1.875 106 270 106 Z F = j 3000 , j 3000 , or 3000 . Plot the % displacement amplitude X 1 of mass M1 when
Homework 2
Acoustics I
due date: October 15, 2007
Shown in Figure 1 is a 1D bar made of steel ( = 7700 Kg / m3 , E = 19.5 1010 Pa , L = 0.2 m). The equation of motion of the bar is given as follows; 2u 2u 2 =E 2 (1) t x where, u is displacement of the ba
Homework 3_rev
Acoustics I
due date: November 19
2007
(1) An expansion chamber muffler is shown below. If, S = a 2 , a is 2 cm, S1 = 20 S , temp = 800 C, calculate and plot the power transmission coefficients T for the muffler with an anechoic termination
Homework 3_rev
Acoustics I
due date: November 19
2007
(1) An expansion chamber muffler is shown below. If, S = a 2 , a is 2 cm, S1 = 20 S , temp = 800 C, calculate and plot the power transmission coefficients T for the muffler with an anechoic termination
Homework 4
Acoustics I
due date: November 26
2007
The figure shown below shows a typical sound power measurement setup in semianechoic chamber (all five surfaces of the room are anechoic, while the floor is rigid. In the figure, Q above the rigid surface
Homework 1 Due date: 10/4/06
Acoustics I
Winter 2006
A SDOF system is operating on a foundation defined by impedance Z F as shown below. Plot the displacement amplitude X 1 at the excitation point as a function of frequency if F
10, 000 0.6 106 30 106 , j