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 Designer-NOISE is a software program designed to allow general and expert
users to quickly and
accurately predict noise levels on surface ship structures. Noise levels in compartments resulting
from various noise paths are calculated and can be analyzed individually or combined. Various
source types can be modeled, including hard and resiliently mounted machinery sources (ranging from
propulsion engines to fan coil units), propellers, and wave slap sources. Treatments common to
ship structures, such as joiner panels, absorptive materials, damping, etc, can be quickly applied
to the model. Analysis results, including octave band and overall compartmental noise levels,
noise levels radiated by each surface in a compartment, radiation efficiencies, transmission loss
values, and more are provided in graphic and tabular format.
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. It uses a 3-D Graphical User Interface (GUI) to facilitate rapid model creation and entry
of model parameters. 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.
Advanced information such as loss factors, Sabine coefficients, etc. are available to the user;
however these parameters do not need to be known in order to create and analyze a model in
Designer-NOISE. As such, Designer-NOISE is a tool that allows users with varying degrees of
acoustical familiarity to create and analyze models.
A general use program such as Designer-NOISE allows complex noise issues to be
addressed early and
throughout the design. 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.
Designer-NOISE can be
used to strike a balance between the selection of machinery and noise control treatment types. The
result will be a lower cost and quicker turn-around design time, lower crew noise exposure, fewer
hearing loss cases, and a lower total cost of ownership. Designer-NOISE has already
been proven to
successfully predict and control noise in complicated designs. Designer-NOISE can
also assist in
mainstreaming the acoustic design process for all types of surface vessels and shipboard noise
problems.
Who can benefit?
In the long run, the ship operator and crews will benefit. In the near term, the shipbuilder
and
designer can produce a quieter product more effectively and efficiently. As naval craft become
lighter and faster, (i.e., LCS, DD-X, & HSV) noise levels will significantly increase due higher
power densities in thinner structures. It will be necessary to develop lighter and more effective
treatments in order to control noise on these platforms without adversely impacting the weight and
speed.
Technology description
 Designer-NOISE
is a modeling tool that utilizes proven acoustic modeling methods. It is built on
acoustic modeling software used by NCE over the last eight years on over two dozen projects. The
prediction accuracy is very high, usually within 2 dB for the A-weighted noise level. This
software utilizes a modified Statistical Energy Analysis (SEA) process to predict the
structureborne induced noise on the vessel. It relies on proven architectural prediction methods
for airborne transmitted noise. The model also utilizes empirical modifications to the standard
SEA and architectural equations that have been derived from years of shipboard verification trials
and diagnostic tests conducted by NCE. These factors come together to create this unique program
specifically designed to analyze ship structures, while allowing it to be used on an unlimited
number of vessel geometries.
 Designer-NOISE
has a Graphic User Interface (GUI) - developed by Proteus Engineering - that greatly
facilitates entering the required structural details: material information, insulation, joiner
panels, treatments, and machinery source levels (noise and vibration). The technical parameters
needed by Designer-NOISE are automatically generated through the creation of common
features such
as decks and bulkheads, and assignment of materials, frame spacing, etc, so the user never needs to
enter complex acoustical data. In addition, source level information is entered using easily
obtainable information (SPL and vibration acceleration) instead of more complex, hard to find
quantities (sound power, vibration power density, etc). Designer-NOISE facilitates
the noise
evaluation and control process for all types of vessels - whether it is early or late in the design
process, or for diagnostic purposes. Furthermore Designer-NOISE is continually
upgraded to keep up
with new sources, materials, and prediction methods.
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.)
Designer-NOISE is a commercially available software package, with pricing starting at
$23,000 per
copy. Limited use demonstration copies are also available. For more information contact Jesse
Spence at jesse@noise-control.com.
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