NEW ORLEANS, May 20, 2025 – Offshore wind farms have the potential for large impacts on clean energy generation, as wind speeds are higher at sea than on land. However, this benefit comes at a high cost for marine life, which can suffer greatly during the installation of offshore wind foundations.
Junfei Li, from Purdue University, will present work on mitigating the noise pollution during monopile offshore wind farm installation Tuesday, May 20, at 1:00 p.m. CT as part of the joint 188th Meeting of the Acoustical Society of America and 25th International Congress on Acoustics, running May 18-23.
This metamaterial structure is made to reduce the noise pollution from undersea monopile foundation construction. Credit: Junfei Li
“To build offshore wind farms, monopile foundations are commonly driven into the seabed with hydraulic impact hammers, generating strong noises that propagate 50 kilometers or more from the installation site, potentially inducing auditory injury and behavioral change in marine species,” said Li.
These deep foundations are crucial for physically supporting wind farms — and other structures — above the sea. Most current mitigation techniques are limited by high energy demands or challenges with transportation and deployment.
Li and his colleagues instead developed a metamaterial comprising of carefully arranged plates that trap air within and act as guides for the sound. With their metamaterial in place, sound from monopile installation can be reduced by 40 decibels, an improvement over the 25-decibel reduction of other methods. The material is modular and foldable, making its transport and deployment easy and inexpensive.
Li said the sounds created during these processes have wide-reaching impacts.
“The high-intensity, impulsive noise generated by pile driving has the potential to affect a range of wildlife — including marine and freshwater fish, sea turtles, and marine mammals,” said Li. “It may lead to a range of behavioral changes in marine mammals and may lead to auditory or physical injury in some species of fish.”
The researchers hope to scale up their technology for deployment in future offshore wind far constructions, as well as for monopiles used in bridge construction and oil drilling platforms.
“Human-generated underwater noise is a critical — yet often hidden — environmental stressor. It’s not just background sound; it actively harms marine life, affecting their ability to survive and thrive,” said Li. “We must acknowledge the severity of our acoustic impact on the underwater world and work toward reducing it.”
ASA PRESS ROOM In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.
LAY LANGUAGE PAPERS ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are summaries (300-500 words) of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.
PRESS REGISTRATION ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting and/or press conferences, contact AIP Media Services at media@aip.org. For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.
ABOUT THE ACOUSTICAL SOCIETY OF AMERICA The Acoustical Society of America is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.
ABOUT THE INTERNATIONAL COMMISSION FOR ACOUSTICS The purpose of the International Commission for Acoustics (ICA) is to promote international development and collaboration in all fields of acoustics including research, development, education, and standardization. ICA’s mission is to be the reference point for the acoustic community, becoming more inclusive and proactive in our global outreach, increasing coordination and support for the growing international interest and activity in acoustics. Learn more at https://www.icacommission.org/.
Instagram: @baglamist
University of Cincinnati, Cincinnati, OH, 45224, United States
Popular version of 2aBAa7 – Measure for measure: Diffraction correction for consistent quantification of bubble-related acoustic emissions
Presented at the 188th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0037529
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
Microscopic bubbles, when caused to vibrate by ultrasound waves, can be powerful enough to break through the body’s natural barriers and even to destroy tissue. Growth, resonance, and violent collapse of these microbubbles, called acoustic cavitation, is enabling new medical therapies such as drug delivery through the skin, opening of the blood-brain barrier, and destruction of tumors. However, the biomedical effects of cavitation are still challenging to understand and control. A special session at the 188th meeting of the Acoustical Society of America, titled “Double, Double, Toil and Trouble – Towards a Cavitation Dose,” is bringing together researchers working on methods to consistently and accurately measure these bubble effects.
For more than 30 years, scientists have measured bubble activity by listening with electronic sensors, called passive cavitation detection. The detected sounds can resemble sustained musical tones, from continuously vibrating bubbles, or applause-like noise, from groups of collapsing bubbles. However, results are challenging to compare between different measurement configurations and therapeutic applications. Researchers at the University of Cincinnati are proposing a method for reliably characterizing the activity of cavitating bubbles by quantifying their radiated sound.
A passive cavitation detector (left) listens for sound waves radiated by a collection of cavitating bubbles (blue dots) within a region of interest (blue rectangle).
The Cincinnati researchers are trying to improve measurements of bubble activity by precisely accounting for the spatial sensitivity patterns of passive cavitation detectors. The result is a measure of cavitation dose, equal to the total sound power radiated from bubbles per unit area or volume of the treated tissue. The hope this approach will enable better prediction and monitoring of medical therapies based on acoustic cavitation.
Figure 1: In an experiment simulating drug delivery through the skin (left), a treatment source projects an ultrasound beam onto animal skin. A passive cavitation detector (PCD) listens for sound radiated by bubbles at the skin surface, while the skin’s permeability is measured from its electrical resistance. Measured bubble activity is quantified using the sensitivity pattern of the PCD within the treated region (highlighted blue circle).
The researchers reported results from two experiments testing their methods for characterizing cavitation. In experiments testing ultrasound methods for drug delivery through the skin (Figure 1), they found that total power of subharmonic acoustic emissions (like musical tones indicating sustained vibrations of resonating bubbles) per unit skin surface area consistently increased when the skin became more permeable, quantifying the role of bubble activity in drug delivery. In a second experiment (Figure 2), the researchers quantified bubble activity during heating of animal liver tissue by ultrasound, simulating cancer therapies called thermal ablation. They found that increased bubble activity could indicate both faster tissue heating near the treatment source and reduced heating further from the source.
Figure 2: An ultrasound (US) array sonicates animal liver tissue with a high-intensity ultrasound beam, causing tissue heating (thermal ablation) as used for liver tumor treatments. Increased bubble activity was found to reduce the depth of treatment, while sometimes also increasing the area of ablated tissue near the tissue surface.
This approach to measuring bubble activity could help to establish standard cavitation doses for many different ultrasound therapy methods. Quantitative measurements of bubble activity could help confirm treatment success, such as drug delivery through the skin, or to guide thermal treatments by optimizing bubble activity to heat tumors more efficiently. Standard measures of cavitation dose should also help scientists more rapidly develop new medical therapies based on ultrasound-activated microbubbles.
The University of Texas at Austin, Austin, TX, 78712, United States
Popular version of 1pSA8 – Magnetostrictive-based Jerk Sensor: experimental characterization and analytical estimation of sensitivity
Presented at the 188th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0037435
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
Researchers at the University of Texas at Austin have developed and tested a new type of accelerometer-a device that measures motion-using a special material called Terfenol-D. This work explores how magnetostrictive materials, which change their magnetic properties when stressed, can be used to sense movement in a simple and reliable way.
How the Sensor Works
The sensor uses a rod of Terfenol-D, a material known for its strong magnetostrictive effect. When the rod is subjected to acceleration (movement), it experiences stress that changes its magnetic state. This change generates a small voltage in a coil wrapped around the rod, which can be measured as an electrical signal. The design uses permanent magnets to provide a steady magnetic field, ensuring the sensor responds in a predictable, linear way.
Key Features and Findings
Sensitive to Jerk: Unlike most motion sensors that respond to acceleration or velocity, this sensor naturally responds to “jerk,” which is the rate of change of acceleration. This means its sensitivity increases with frequency up to its first resonance, making its performance in terms of signal to noise ratio to excel as frequency increases.
Low Output Impedance: The sensor produces signals that can be easily transmitted over long cables without losing strength, unlike some traditional accelerometers that require extra electronics to preserve signal strength.
No External Power Needed: The sensor generates its own signal from motion, so it does not require an active power supply for operation, making it suitable for remote or hard-to-reach locations. The design avoids complex parts, which could make it easier and less expensive to manufacture.
Testing and Performance
The team tested the sensor using two methods: vibrating it with a piezoelectric device and striking a plate with a specialized hammer. In both cases, the sensor’s output matched well with predictions from computer models and theoretical calculations. The sensor demonstrated a low noise floor (the smallest signal it can reliably detect), comparing favorably with commercial accelerometers.
Measurement setup using automatic modal hammer for vibrating the sensor.
Potential Applications
Seismic and Underwater Sensing: The sensor’s design is promising for applications such as seismic monitoring or underwater acoustic sensing, where devices may need to operate for long periods without maintenance or external power.
Large-Scale Sensor Networks: Its simplicity and self-powered operation make it a good candidate for use in networks of sensors spread over wide areas, such as for environmental monitoring.
Next Steps
The researchers plan to further develop this technology for underwater use, where measuring motion accurately is essential for applications like underwater navigation or monitoring ocean conditions.
Funding
This research was supported by the Office of Naval Research.
Contact
For more information, contact Ehsan Vatankhah at the Chandra Family Department of Electrical and Computer Engineering, University of Texas at Austin.
MELVILLE, N.Y., Nov. 21, 2024 – Fossils might give a good image of what dinosaurs looked like, but they can also teach scientists what they sounded like.
The Parasaurolophus is a duck-billed dinosaur with a unique crest that lived 70 million to 80 million years ago. It stood around 16 feet tall and is estimated to have weighed 6,000 to 8,000 pounds.
A 3D-printed model of the Parasaurolophus skulls at a 1:3 scale to the original fossil. The white model is the nasal passages inside the skull. Credit: Hongjun Lin
Hongjun Lin from New York University will present results on the acoustic characteristics of a physical model of the Parasaurolophus’ crest Thursday, Nov. 21, at 4:30 p.m. ET as part of the virtual 187th Meeting of the Acoustical Society of America, running Nov. 18-22, 2024.
“I’ve been fascinated by giant animals ever since I was a kid. I’d spend hours reading books, watching movies, and imagining what it would be like if dinosaurs were still around today,” said Lin. “It wasn’t until college that I realized the sounds we hear in movies and shows—while mesmerizing—are completely fabricated using sounds from modern animals. That’s when I decided to dive deeper and explore what dinosaurs might have actually sounded like.”
Lin created a physical setup made of tubes to represent a mathematical model that will allow researchers to discover what was happening acoustically inside the Parasaurolophus crest. The physical model, inspired by resonance chambers, was suspended by cotton threads and excited by a small speaker, and a microphone was used to collect frequency data.
While it isn’t a perfect replication of the Parasaurolophus, the pipes—nicknamed the “Linophone,” after the researcher—will serve as a verification of the mathematical framework.
“I wanted something simplified and accessible for both modeling and building a physical device,” Lin explained.
Lin’s initial results indicate that the Parasaurolophus’ crest was used for resonance, similar to the crests of birds we see today. The mathematical model is still in progress, but Lin hopes it will be useful for studying animals with similar vocal structures.
He is also planning to create an accessible plug-in for people to experiment with and even add dinosaur sounds to music.
“Once we have a working model, we’ll move toward using fossil scans,” Lin said. “My ultimate goal is to re-create the sound of the Parasaurolophus.”
ASA PRESS ROOM
In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.
LAY LANGUAGE PAPERS
ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are summaries (300-500 words) of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.
PRESS REGISTRATION
ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the virtual meeting and/or press conferences, contact AIP Media Services at media@aip.org. For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.
ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.
Sandia National Laboratories, Albuquerque, NM, 87185, United States
Additional authors:
Cameron McCormick and Benjamin Treweek
Popular version of 1aSA6 – Acoustic Black Hole Effect Due to Variation in Duct Wall Impedance
Presented at the 187th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0034973
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
Consider a black hole in outer space, where gravity is so strong that not even light waves can escape. Now, imagine a device here on Earth that can slow sound waves so much that they cannot escape. Scientists call this intriguing phenomenon an “acoustic black hole” (ABH). An ABH structure can trap sound waves and produce a unique environment for acoustic measurement and manipulation.
How can a structure be designed to trap sound in this way? The acoustic black hole effect is achieved by altering the way sound travels down a duct. Traditional ABHs are based upon the pioneering research of Mironov and Pislyakov (2002) that used specific shapes to guide sound waves, such as rings with inner radii that vary down the length of the duct. However, in this work, the approach is different: varying the mechanical impedance of the duct walls themselves (see Figure 1). Mechanical impedance refers to how much a structure resists motion when sound waves press against it. By engineering an impedance profile—essentially, the way the walls respond to sound throughout the duct—researchers can create a situation where sound waves decrease in speed as they travel through the duct. A gradual reduction in speed effectively simulates the event horizon of a black hole, causing the sound waves to be trapped and significantly attenuated (see Figure 2).
Figure 1. A sound wave enters a duct where the walls are stiffer at the entrance and softer at the base. As the wave moves through the duct, it slows down due to the changing properties of the walls.
To better understand this phenomenon, the researchers derived and solved governing equations using two methods. First, they used a mathematical technique called the WKB approximation, which helps find approximate solutions to wave equations. Second, they used numerical simulation, which involves using computers to model complex systems. The solutions they obtained from these approaches revealed that specific impedance profiles could effectively decelerate and absorb acoustic waves, resulting in very little reflection or transmission of sound.
To verify their findings, the researchers employed a sophisticated program called Sierra/SD. This program uses a fully coupled structural-acoustic finite element algorithm. In brief, this algorithm allows researchers to create a computer model of any design they want and test how it responds to any sound source. This tool allows for detailed simulations of how sound interacts with various structures and provides a robust framework for testing theoretical predictions.
Overall, this research not only enhances understanding of the acoustic black hole effect, but also paves the way for the development of innovative acoustic materials and devices. By using the principles of ABH, these advancements could lead to improved noise control and enhanced manipulation of sound waves, with potential applications in various fields such as engineering, architecture, and environmental science.
Figure 2. An illustration of a sound wave vanishing in an acoustic black hole structure. The ABH effect is seen from the wavefronts becoming closer together (slower sound speed) and lower in amplitude (lower peaks, higher troughs) at the right end.
Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA-0003525.
Department of Interior Architecture and Environmental Design, Bilkent University, Ankara, Turkey, 06800, Turkey
Ela Fasllija, Enkela Alimadhi, Zekiye Şahin, Elif Mercan, Donya Dalirnaghadeh
Popular version of 5aPP9 – A Corpus-based Approach to Define Turkish Soundscape Attributes
Presented at the 184 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0019179
We hear sound wherever we are, on buses, in streets, in cafeterias, museums, universities, halls, churches, mosques, and so forth. How we describe sound environments (soundscapes) changes according to the different experiences we have throughout our lives. Based on this, we wonder how people delineate sound environments and, thus how they perceive them.
There are reasons to believe there may be variances in how soundscape affective attributes are called in a Turkish context. Considering the historical and cultural differences countries have, we thought that it would be important to assess the sound environment by asking individuals of different ages all over Turkey. For our aim, we used the Corpus-driven approach (CDA), an approach found in Cognitive Linguistics. This allowed us to collect data from laypersons to effectively identify soundscapes based on adjective usage.
In this study, the aim is to discover linguistically and culturally appropriate equivalents of Turkish soundscape attributes. The study involved two phases. In the first phase, an online questionnaire was distributed to native Turkish speakers proficient in English, seeking adjective descriptions of their auditory environment and English-to-Turkish translations. This CDA phase yielded 79 adjectives.
Figure 1 Example public spaces; a library and a restaurant
In the second phase, a semantic-scale questionnaire was used to evaluate recordings of different acoustic environments in public spaces. The set of environments comprised seven distinct types of public spaces, including cafes, restaurants, concert halls, masjids, libraries, study areas, and design studios. These recordings were collected at various times of the day to ensure they also contained different crowdedness and specific features. A total of 24 audio recordings were evaluated for validity; each listened to 10 times by different participants. In total, 240 audio clips were randomly assessed, with participants rating 79 adjectives per recording on a five-point Likert scale.
Figure 2 The research process and results
The results of the study were analyzed using a principal component analysis (PCA), which showed that there are two main components of soundscape attributes: Pleasantness and Eventfulness. The components were organized in a two-dimensional model, where each is associated with a main orthogonal axis such as annoying-comfortable and dynamic-uneventful. This circular organization of soundscape attributes is supported by two additional axes, namely chaotic-calm and monotonous-enjoyable. It was also observed that in the Turkish circumplex, the Pleasantness axis was formed by adjectives derived from verbs in a causative form, explaining the emotion the space causes the user to feel. It was discovered that Turkish has a different lexical composition of words compared to many other languages, where several suffixes are added to the root term to impose different meanings. For instance, the translation of tranquilizer in Turkish is sakin-leş (reciprocal suffix) -tir (causative suffix)- ici (adjective suffix).
The study demonstrates how cultural differences impact sound perception and language’s role in expression. Its method extends beyond soundscape research and may benefit other translation projects. Further investigations could probe parallel cultures and undertake cross-cultural analyses.
A passive cavitation detector (left) listens for sound waves radiated by a collection of cavitating bubbles (blue dots) within a region of interest (blue rectangle).
Figure 1: In an experiment simulating drug delivery through the skin (left), a treatment source projects an ultrasound beam onto animal skin. A passive cavitation detector (PCD) listens for sound radiated by bubbles at the skin surface, while the skin’s permeability is measured from its electrical resistance. Measured bubble activity is quantified using the sensitivity pattern of the PCD within the treated region (highlighted blue circle).
Figure 2: An ultrasound (US) array sonicates animal liver tissue with a high-intensity ultrasound beam, causing tissue heating (thermal ablation) as used for liver tumor treatments. Increased bubble activity was found to reduce the depth of treatment, while sometimes also increasing the area of ablated tissue near the tissue surface.
Measurement setup using automatic modal hammer for vibrating the sensor.
Figure 1. A sound wave enters a duct where the walls are stiffer at the entrance and softer at the base. As the wave moves through the duct, it slows down due to the changing properties of the walls.
Figure 2. An illustration of a sound wave vanishing in an acoustic black hole structure. The ABH effect is seen from the wavefronts becoming closer together (slower sound speed) and lower in amplitude (lower peaks, higher troughs) at the right end.
