Saturn Enterprises, Inc.

Acoustical Duct Lining

Problem:

ATTENUATION OF 10' OF DUCTWORK (LINED VS. UNLINED)
	1	2	3	4	5	6	7	8
24" by 24" unlined	2	2	1	0	0	0	0	0
24" by 24" 1" liner	3	3	6	15	29	25	21	19
24" by 24" 2" liner	3	5	11	31	29	25	21	19

Ductwork is often internally lined in order to attenuate the sound traveling down it (see chart). By adding a liner to the ductwork the sound can be attenuated, but the low frequency sounds are not affected nearly as much as the higher ones. This leads to lots of low frequency noise being transmitted to the served spaces, which the user then perceives as a rumble.

Also, as ductwork gets larger in size, the P/A ratio goes up. The P/A ratio relates duct perimeter to duct cross sectional area, and is used to determine the attenuation of the ductwork. As the ratio goes up, the attenuation of both lined and unlined ductwork goes down considerably.

Solution:

By using a RINK silencer as an alternative to lined ductwork, this low frequency sound can be attenuated along with the other frequencies. This is a better solution than the duct lining for many reasons. First, as can be seen below, the RINK silencer provides superior attenuation in just 5' of run vs. the 10' of lined ductwork. Second, RINK silencers typically cost less than internal duct lining, both in initial cost and installation cost. Third, RINK silencers have a lower chance of having glass fiber erosion than an internally lined duct (consider also the option of Mylar encapsulated lining). Finally, RINK silencers are easier to clean than long lengths of internally lined ductwork.


Saturn Enterprises, Inc.
Leading Supplier of HVAC Products for the Global Market

Leading Supplier of HVAC Products for the Global Market