A workshop of six similar internal surfaces possesses a reverberation time of 3 sec. The dimension of the workshop is 18 m x 10 m x 6 m. A machine is operated inside the workshop that has a sound power level of 80 dB and a directivity factor, Q = 2. To reduce the noise level within the workshop, the following noise treatment are applied on the workshop internal surface a) Ceiling covered with material of absorption coefficient = 0.7 b) Both long walls covered with material of absorption coefficient = 0.8 Determine the following: The average absorption coefficient of the workshop surfaces with the noise treatment

A workshop of six similar internal surfaces possesses a reverberation time of 3 sec. The dimension of the workshop is 18 m x 10 m x 6 m. A machine is operated inside the workshop that has a sound power level of 80 dB and a directivity factor, Q = 2. To reduce the noise level within the workshop, the following noise treatment are applied on the workshop internal surface a) Ceiling covered with material of absorption coefficient = 0.7 b) Both long walls covered with material of absorption coefficient = 0.8 Determine the following: The average absorption coefficient of the workshop surfaces with the noise treatment

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.2DP

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