is an Air Handling Unit (AHU) Mockup Test?
a terminal unit mockup test, an air handling unit mockup assembly
is designed to measure noise made by mechanical equipment. The mockup
enables the owner and project team to experience the noise levels
as they would be in the space, and if necessary, make refinements
to the architectural and mechanical elements of the design. In high-rise
buildings that typically have floor mechanical equipment
rooms, it is essential to understand the acoustical ramifications
of the proposed design even so far as they relate to compliance with
tenant lease agreements.
is an AHU Tested?
The mockup for testing an air handling
unit is actually an assembly consisting of one or more offices adjacent
to a mechanical room which houses a floor AHU typical to the project.
In the test, airflow is delivered both at the design operating conditions
and at various percentages of the design-day air flow. To insure
that the testing is accurate, air quantities are read from air measuring
stations. At each test point, peak and average sound pressure levels
are noted at each octave band frequency. Test results are then plotted
on NC curves to establish the unit's acoustical performance based
on NC ratings relative to the project's Design Criteria.
We recently performed an AHU mockup
test for one manufacturer in which we tested a 16,500 CFM air handling
unit using supply ductwork constructed of five different sheet metal
gauges. The ducts were the same overall length, constructed in the
same five-foot lengths with joints and angle reinforcements identically
placed. Four were standard unlined ducts in different gauges. For
the fifth specimen we used one of the first four ducts but enhanced
it. We then tested each unit at different airflow and pressure conditions.
The results provided the client with a clear indication of which
duct achieved the required NC at a specific airflow level.
Mockup Room Testing