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 What is Designer-NOISE™? Designer-NOISE™ is a software program designed to allow
for quick and accurate predictions of noise levels on surface ships and other stiffened plate
structures. Octave-band and overall A-weighted noise levels are calculated based on sound
propagation from machinery, propeller, and wave slap sources via airborne and structureborne
paths. Nearly any machinery source can be modeled, ranging from propulsion engines to fan
coil units. HVAC analyses can also be performed, and the resulting noise levels can be
combined with machinery noise results. Most importantly, the causes of noise in any
compartment can be evaluated, and various treatment options can be explored, including
resiliently mounting equipment, adding absorptive insulation and/or damping materials, etc.
By using Designer-NOISE™ treatments can be quickly optimized to meet acoustic goals while
minimizing impacts to space, weight, and cost.
Designer-NOISE™ was created under a US Navy Small Business Innovative Research (SBIR)
program, N98-092, with the guidance and support of Mr. Kurt Yankaskas of Human Systems
Integration group at NAVSEA.
Who can benefit? In the short term, Designer-NOISE™ can allow shipbuilders and designers to
produce quieter vessels more effectively and efficiently. Noise can be analyzed early in the
design process to help with the overall design of the vessel, equipment selection, and treatment
requirements. Furthermore, modifications to the vessel that occur as the design progresses can
be assessed from a noise perspective, allowing for a more complete cost benefit analysis. In
the long run, ship operators and crews will benefit as a result of lower noise levels leading to
increased productivity, lower fatigue, and a reduced risk of long-term hearing damage, leading to
lower cost of ownership. With the proper attention paid to noise by the marine community in
general, the noise levels onboard ships can be significantly decreased and noise control treatments
can be optimally designed with respect to acoustic and non-acoustic parameters.
 How does it work?
Designer-NOISE™ uses a 3-D Graphical User Interface (GUI) to facilitate rapid model creation and
entry of model parameters. The 3-D GUI provides the user with a more intuitive and realistic
representation of the vessel, and allows for improved 'bookkeeping' as compared with spreadsheet
methods. The core solver uses a hybrid Statistical Energy Analysis approach to predict spreading
of vibration throughout the vessel. Architectural acoustic methods are used to predict the
spreading of airborne noise. Solution time for most models is on the order of seconds, allowing
the user to perform rapid tradeoff studies of potential noise control treatments, sources, etc.
The prediction accuracy is very high, usually within 3 dB for A-weighted noise levels.
What does it take to build a model? Models can typically be created in a matter of
days once the appropriate information has been obtained. Inputs are straight-forward, physical
property information such as material types, thicknesses, frame spacing, etc. The acoustical
properties and effectiveness of many materials and treatments are incorporated into the program,
eliminating the need for specific user knowledge of acoustical details. Models are initiated by
assigning planes and surfaces at appropriate locations to represent decks and bulkheads.
Physical properties are then assigned to each modeled face, such as structural material, plating
thickness, stiffener spacing, etc. Outfitting such as thermal and fire insulation and joiner
facings are then assigned, along with any acoustical treatments. Sources are added by defining
the physical size and location, as well as acoustical source levels (sound pressure levels and
vibration acceleration). Because Designer-NOISE™ is meant specifically for modeling ship noise,
all inputs have been streamlined to reduce the total amount of information required by the user.
To see an example of how Designer-NOISE™ is used, see the example movies below.
 How do I assess the
results? Octave band and overall A-weighted noise levels are reported for any compartment of
interest, and can be compared to a user-defined criteria. This information can be used to assess
if the compartment meets or exceeds its noise goal. For those compartments that do not meet their
noise limits, the results can be provided for individual sources to help the user identify which
source(s) contribute the most in a given location. The results are also broken down by path
(airborne, structureborne, and secondary structureborne) to show how the sound is getting from
source to receiver. This information is invaluable in determining an appropriate noise control
approach. Additional information that is useful in determining appropriate treatments and
treatment locations are provided in detailed spreadsheet reports. This information includes a
breakdown of the contribution of each surface to the sound produced in each compartment,
radiation efficiencies and treatment effectiveness, vibration levels on all surfaces, and other
detailed acoustical information such as damping and coupling loss factors. After assessing
the available information, an informed choice of appropriate treatment options can be determined
and tested for effectiveness. Tradeoff studies of different treatment combinations can be
performed rapidly through the quick assignment of treatments and fast model solution times.
Example Movies
The following downloadable movies offer a brief overview of the capabilities of Designer-NOISE™,
as well as the modeling process and speed with which models are created and analyzed.
To see Designer-NOISE™ in operation, download one of the three following movies::
(Click on a link to open the movie in a new window or right click to download to
your computer.)
Pricing
Designer-NOISE is a commercially available software package, with pricing starting at $23,000
USD per copy.
Request a Demo Copy
Limited use demonstration copies are available. For more information contact Jesse Spence at
jesse@noise-control.com.
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