Acoustics of Intakes and Exhausts
Non-Linear and Linear Modeling of Intake and Exhaust Noise
Intake and exhaust system acoustic modeling is one of the more common application areas in which GT-POWER is used. The objective of this analysis is to predict the gas pulsation generated noise emanating from the intake and/or exhaust opening (snorkel or tailpipe).
Acoustic modeling in GT-POWER is very easily accomplished by simply adding a microphone modeling element to the existing engine model. Acoustic characteristics of the intake/exhaust noise will then be automatically computed and presented in terms of order cuts, order and frequency based carpet plots, and Campbell diagrams. The user may also request the creation of an audio output file that can be used to make subjective and sound quality assessments of the predicted intake/exhaust note. In this manner, the "right sound" of the vehicle can be designed into the engine at an early stage in the design process.
The 4 links below are examples of audio files created by GT-POWER simulations
Engine Accelerating:
Truck Idling:
Open Wheel Race Engine-Driveby:
Motorcycle Shifting:
Aiding the engineer in the development of models for acoustic analysis, GT-POWER includes a built-in CAD based preprocessor known as GEM3D (Geometric Element Modeler), which is a full, 3D, CAD kernel modeling tool that makes building models of complicated mufflers, resonators, and general piping networks fast and easy. GEM3D can be used to either import existing CAD data and mesh it into a GT-POWER model, or to start from a clean sheet of paper, and design entirely new concepts from scratch. The developed models are then automatically meshed into a compatible GT-POWER model for physical computation. The process reduces the time required to build models of complicated geometries from many hours to minutes, and the automatic mesh generation eliminates the chance for user error often introduced via the tedious process of manually creating such meshes.
Image of exhaust muffler in GEM3D
Standard GT-POWER acoustic analysis is accomplished within an engine model utilizing GT-POWER's highly efficient explicit (fully nonlinear) solver. For simple concept studies, GT-POWER also includes a classical linear acoustics solver, which can be used for very rapid component and silencing module design and analysis. The linear solver is applicable to common silencing elements such as Helmholtz resonators, quarter wave tubes, expansion cans, pipe perforates, and other classical silencing elements, and provides results in a matter of seconds.
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 For more information contact:(or contact us online) |
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| Gamma Technologies, Inc. 601 Oakmont Lane, Suite 220 Westmont, IL 60559 USA |
Tel. Fax. (630) 325-5849 Email: CAE@gtisoft.com Web: www.gtisoft.com |
APPLICATIONS
Engine Performance
Test Pressure Analysis
Exhaust Aftertreatment
Acoustics
SiL, HiL, real-time
Vehicle, driveline
Hybrid Vehicles
Cooling/VTM
Underhood Modules
AC and Rankine
Lubrication and bearings
Fuel Injection
Hydraulics, pneumatics
Valvetrain, camshaft
Cranktrain, crankshaft
Chain, gear, belt drive