ASHRAE 68 : 0
Withdrawn
A Withdrawn Standard is one, which is removed from sale, and its unique number can no longer be used. The Standard can be withdrawn and not replaced, or it can be withdrawn and replaced by a Standard with a different number.
LABORATORY METHOD OF TESTING TO DETERMINE THE SOUND POWER IN A DUCT
02-29-2016
Foreword
1 Purpose
2 Scope
3 Definitions and Symbols
4 Measurement Uncertainty
5 Test Facilities and Instrumentation
6 Test Setup
7 Test Procedure
8 Calculations
9 References
TABLES
1 Estimated Standard Deviations
2 Maximum Reflection Coefficient
3 Frequency Response Correction C2
4 Flow Velocity Correction C3
5 Modal Correction C4
FIGURES
1A Test on Fan Outlet with Open Inlet
1B Test on Fan Outlet with Ducted Inlet
1C Test on Fan Inlet with Open Discharge
1D Test on Fan Inlet with Ducted Discharge
APPENDICES
A Estimation of Testing Accuracy
B Anechoic Termination
C Throttling Section Suggestions
D Example Calculations
E Turbulence Screen and Typical Mountings of
Microphone and Sampling Tube
F Determination of the Signal-to-Noise Ratio of
Sound to Turbulence Noise in the Test Duct
G Bibliography
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