ResearchNPL's Acoustics group undertakes long-term, leading-edge research to develop new and improved measurement methods that will impact on future UK services and products.
NPL provides world-class standards for measurement and calibration, and undertakes measurement related research and development, in three main areas within Acoustics:
For more information please contact acoustics_enquiries@npl.co.uk
- Technical Guides on Sound in Air, Ultrasonics and Underwater Acoustics.
- NPL provides input to the working groups of international and national standards bodies and is aiding development of internationally standardised methods for testing DSP hearing aids.
- A guide for all parties who commission, undertake or use environmental sound predictions for commercial or industrial operations, of whatever type or scale, for which an environmental noise assessment may be required.
- NPL is pursuing the development of MEMS (Micro Electro-Mechanical System)-based measurement microphones.
- Secondary calibration of working standard microphones can offer the most direct and cost-effective traceability path for sound-in-air measurements.
- Research work is currently being undertaken towards the development of a new optically-based primary standard for the free-field calibration of airborne measuring instruments based on photon correlation spectroscopy.
- NPL provides primary measurement standards appropriate for the wide range of acoustical measurements in air. These standards support sound pressure measurements for manufacturing and product QA, health, safety and hearing conservation, environment noise measurement and monitoring, and many other applications.
- NPL offers guidance on acoustic emission measurements and calibration, and carries out measurements for customers on a consultancy basis.
- Technical Guides on Sound in Air, Ultrasonics and Underwater Acoustics.
- There is a clear need to develop reliable methods for quantifying cavitation occurring in flow systems, which should lead to extensive energy savings through better pump selection, installation and operation.
- Technical guide on the use and selection of acoustic emission sensor couplants.
- Leading-edge research investigating development of techniques for determining acoustic cavitation in industrial high power ultrasonic fields.
- Determining the acoustic output of medical devices is essential for manufacturers to demonstrate standards compliance, but is also important in prototype evaluation and type testing.
- NPL provides services for hospitals and industry, through the calibration of radiation force balances for determining ultrasonic output power, and the measurement of ultrasonic power itself, produced by customer systems ranging from prototype transducers to reference sources.
- The NMS primary standard for hydrophone calibration, the laser interferometer, will continue to be provided, alongside measurement facilities used to disseminate hydrophone calibration services to the user community.
- Technical Guides on Sound in Air, Ultrasonics and Underwater Acoustics.
- The increasing level of man-made sound in the ocean (whether deliberately generated or not) has led to concern over marine noise pollution.
- Research into a new optically-based primary standard for the calibration of underwater hydrophones for direct and absolute calibration of hydrophones, directly related to the unit of acoustic sound pressure.
- Data describing the variation in performance of commercially available hydrophones with temperature and depth have until now been difficult to obtain and are not readily available from hydrophone manufacturers.
- This shows performance data for a number of commercially available hydrophones that have been characterised at various simulated ocean conditions.
- NPL's Acoustics Pressure Vessel can be used to simulate ocean conditions and support various measurements.
- NPL is currently working on the development of techniques to predict the far-field response from measurements made in the acoustic near-field.
- Details on various underwater acoustics standards, including free-field hydrophone at different frequency ranges.