Nor 1517

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Nor 1517

• Measurement of Specific Airflow Resistance
• Ole-Herman Bjor Norsonic AS

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Nor 1517
Air flows out
Air flows in
Airflows resistivity Pas/m3
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Nor 1517
Airflows resistivity Pas/m3
Specific airflows resistance Pas/m
Airflows resistivity Pas/m2
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Nor 1517
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Nor 1517
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Nor 1517
A area of test specimen d thickness of test
specimen p sound pressure observed by the
microphone Pa f frequency of excitation,
nominal value 2 Hz Ap area of the piston,
nominal value h peak-to-peak amplitude of the
piston movement V volume of the vessel Pa
atmospheric air pressure ? ratio of specific
heat Cp/Cv for air, nominal value 1,4.
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Nor 1517
Air flows in
Air flows out
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Nor 1517
Air flows in
Air flows out
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Nor 1517
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Nor 1517
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Nor 1517

• Heat conduction

Adiabatic compression
Isoterm compression
Correction corresponds to 0,16 dB
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Nor 1517
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Nor 1517

• Mount the calibration disc and start the motor of
  Nor1517.
• Read the displayed level for the 2 Hz filter band
  and adjust the sensitivity if required.
• Offset the calibration by subtracting 46,1 dB
• Set Nor140 to display engineering units (EU)
• Switch off the motor and replace the calibration
  disc with the material to be tested.
• Read the specific airflow resistance from the
  display.

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Nor 1517

Direct readout of specific airflow
resistance 269 269 Pas/m 90.7k 90700 Pas/m
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Nor 1517

• Measurement according to ISO 9053.
• Direct reading of specific airflow resistance.
• One large measurement range 4 5 decades.
• Calibration level included in measurement range.