Vibroacoustic Tests: Exploring the Dynamics of Sound and Vibration

What are Vibroacoustic Tests?

Vibroacoustic tests are specialized procedures that are used to analyze the interaction between mechanical vibrations and acoustic output in various systems. These tests provide crucial insights into the structural integrity, performance, and efficiency of machinery, equipment, and devices across different industries.

Basic Concepts and Definitions

Understanding the fundamentals of vibroacoustics is essential for comprehending the principles behind vibroacoustic testing. From resonance and frequency analysis to noise and vibration control, grasp the key concepts that underpin this interdisciplinary field.

History and Development of Vibroacoustic Tests

The origins of vibroacoustic testing can be traced back to the early 20th century when engineers and scientists began exploring the relationship between mechanical vibrations and acoustic emissions. Over the decades, advancements in technology, such as the development of sophisticated sensors and signal processing techniques, have revolutionized the field, enabling more accurate and comprehensive testing methodologies.

Key Measurement Methods and Techniques in Vibroacoustics

Vibroacoustic tests employ a variety of measurement methods and techniques to assess the dynamic behavior of systems under different operating conditions. From modal analysis and frequency response testing to acoustic intensity mapping and vibration isolation. The following list of testing methods presents our framework:

• endurance tests: sinus, random, shock, SRS
• operational and experimental modal anlaysis,
• teoretic modal analysis – simulations
• Operational Deflection Shape,
• Buzz, Squeak & Rattle testing
• dynamic measurements
• FFT vibration spectral analysis

Application of Vibroacoustic Testing

Vibroacoustic testing finds applications in a wide range of industries, including automotive, aerospace, manufacturing, and healthcare.

Automotive industry is one of the most important area for vibroacoustic testing. Thanks to it, we can evaluate the performance of a vehicle in its key points: Total interior noise, brake noise road noise and component performance

Same is the role of vibroacoustic testing in machinery. This type of research allows assessing  the operating culture of machines, predict possible faults, and obtain information on what design changes should be introduced to reduce noise or modify its acoustic footprint.

Our field of expertise is also vital for a construction industry. Acoustic tests are used to determine the acoustic parameters of building elements. However, the combination of vibration and acoustic pressure tests is used for vibroacoustic analyzes of products and, in a further step, to optimize them in terms of acoustics.

Vibroacoustics in Diagnosing Machines and Devices

One of the primary purposes of vibroacoustic testing is to diagnose potential faults and anomalies in machinery and devices. By analyzing the vibrational and acoustic signatures of equipment, engineers can identify issues such as bearing wear, imbalance, and misalignment, enabling timely maintenance and repair actions to be taken. Due to the nature of these kinds of malfunction it is best to gather as much data as possible and use it as a learning material. Therefore, vibroacoustic testing becomes a gateway to the process called ,,Predictive maintenance”, the future of product development and life cycle management. It means that the data extracted from the testing is put into an analysis to identify operational anomalies and potential equipment defects, enabling timely repairs before failures occur.

Such a case perfectly underlines the role of vibroacoustic testing in the development of machinery

The Impact of Vibroacoustics on Product Design

Integrating vibroacoustic testing into the product design process can lead to significant improvements in performance, durability, and user experience. By optimizing the structural dynamics and minimizing noise and vibration levels, designers can create products that meet the highest standards of quality and reliability.

Software and Tools Supporting Vibroacoustic Research

A variety of software packages and tools are available to support vibroacoustic research and analysis. From finite element analysis (FEA) software to acoustic simulation tools. The list of most important software we use in our daily task are mainly the following:

• Artemis HeadAcoustics (Audio)
• Comsol Multiphysics (FEM)
• VA One (SEA)
• TestLab (Vibration)
• Software for architecture (Odeon, SONArchitect, Insul)
• Environmental noise analysis software (CadnaA)

New Directions and the Future of Vibroacoustics

As technology continues to evolve, so too will the field of vibroacoustics. From the development of advanced testing methodologies to the integration of artificial intelligence and machine learning techniques. The latter is our main scope of interest and research. KFB’s R&D team is currently involved in a project called the System for monitoring and identification of vibroacoustic threats. Thanks to artificial intelligence algorithms, it will essentially allow a big leap into the next level of acoustic analysis, by doing the following:

• Automatically identifying acoustic events in real time and informing on an ongoing basis about identified events,
• Indicating the approximate location of the events,
• Displaying the exact timing of acoustic events.

This is a significant advantage compared to other solutions, such as microphone arrays and intensity probes, where it is possible to determine only the direction of the arrival of the acoustic wave.

Moreover, the available alternatives do not offer automatic event identification and are therefore incomplete alternatives. The implementation of the system will be based on a network of intelligent sensors, able to communicate not only with the central unit, but also with each other.

Examples of application would include a variety of instances, mainly: environmental acoustics, industrial installations, monitoring the operation of machines and devices.

Vibroacoustics and Environmental Protection – Noise and Vibration Reduction

In addition to improving product performance and reliability, vibroacoustic testing plays a crucial role in minimizing environmental impact by reducing noise and vibration emissions.

These tests are a part of an expanded process that also includes testing, modeling, and consulting services for understanding environmental noise. This interdisciplinary approach helps us to identify and analyze the primary site noise sources, and to develop treatment plans to mitigate environmental noise impact. Therefore, vibroacoustic testing plays crucial role in maintaining low noise exposures and enable organizations to be in charge of their industrial impact by implementing noise control and noise management solutions.

Why are Vibroacoustic Tests Important for Modern Technology?

In today’s fast-paced and competitive business environment, the ability to ensure the quality, reliability, and safety of products is paramount. This is precisely why one of the most important KFB Acoustic’s areas of activity is a TIC sector.

TIC – Testing, Inspection and Certification sector provides assessment services, i.e. testing, validation, declaration of conformity, etc., for the purpose of regulatory reasons or good practice.

ARIC, or Acoustic Research and Innovation Center, a heart of our research and testing capabilities consists of both reverberation and anechoic chambers, forming a dedicated testing grounds to accurately assess various types of equipment. For example, construction industry is required to have its products manufactured according to strict international standards.

Answering to this demand and thanks to the obtained Accreditation For Testing Laboratory (No AB 1271) we can:

• measure the acoustic insulation of airborne sounds, ensuring products comply with international standards such as ISO 10140-2 and ASTM E90 for the US market and
• verify sound power levels in accordance with standard ISO 3741.

Vibroacoustic Testing – Who Performs It?

Vibroacoustic testing is typically conducted by trained engineers and technicians with expertise in structural dynamics, acoustics, and vibration analysis. Depending on the complexity of the testing requirements, organizations may choose to perform testing in-house using their own facilities and equipment or outsource it to specialized testing laboratories.

Vibroacoustic Tests – Where to Perform Them?

Vibroacoustic testing can be performed in a variety of settings, ranging from dedicated testing facilities equipped with modern instrumentation to on-site locations such as manufacturing plants, research laboratories, and field sites. The perfect example of a testing facility developed by an engineering company is ARIC (Acoustic Research and Innovation Center) in Wrocław. The facility, established by KFB Acoustics develops opportunities for acoustic technologies in industry and environment. It is a comprehensive