Intense Noise (Acoustic) Test
(NOISE 501)
Overview for management and participants
- Relationship of acoustics to other environments, specifically vibration and shock
- Types of dynamics tests and their applications
- Approximate scheduling of class topics
Assessment of attendee background and prior knowledge of dynamics
Review of vibration concepts
- Classical sinusoidal vibration: natural frequency, damping, structural resonant behavior, fatigue, isolation
- Random vibration: sources, terminology, statistical applications
- Introduction to spectrum analysis: comparison of time and frequency domain analyses
- "Equivalence" of sine and random vibration
- Relationship between vibration and acoustic environments
Instrumentation used in flight and ground dynamic testing
- Transducers: accelerometers, microphones, strain gages
- Calibration of transducers and systems, by vendor vs. on-site
- Signal conditioning and recording/processing equipment
- Tolerances and errors
Intense noise test practice
- Design and use of reverberant and/or progressive-wave acoustic chambers
- Installation of test article in chamber
- Noise generation requirements
- Chamber calibration; empty chamber spectrum, effects of test article volume, differences between "identical" flight and test environments
- Control of test input: number, location and orientation of control microphones
- Acquiring test data using microphones, accelerometers, other sensors
- Dynamic ranging
- Safety/abort systems
- Data presentation
- Interpreting and implementing acoustic test standards; tolerances
- Witnessing tests
Combined environment (CERT) testing; reliability tests, e.g. MIL-STD-781
Course summary; optional final examination; award of certificates
