Projects / Programmes
Noise control and its efect on people
January 1, 2013
- December 31, 2016
| Code |
Science |
Field |
Subfield |
| 2.03.04 |
Engineering sciences and technologies |
Energy engineering |
Energy systems |
| 1.08.00 |
Natural sciences and mathematics |
Control and care of the environment |
|
| Code |
Science |
Field |
| T210 |
Technological sciences |
Mechanical engineering, hydraulics, vacuum technology, vibration and acoustic engineering |
| Code |
Science |
Field |
| 2.02 |
Engineering and Technology |
Electrical engineering, Electronic engineering, Information engineering |
| 1.05 |
Natural Sciences |
Earth and related Environmental sciences |
Researchers (12)
Organisations (3)
Abstract
Noise is a drawback of our civilization. Excessive noise damages hearing and causes a number of psycho-physiological disorders. It also affects work efficiency. Noise is an issue that concerns both the protection of the environment and the humanization of working place. In addition to traffic, the most common causes of noise both at workplace, and in the natural and living environment are machinery and equipment. If a machine generates excessive noise levels, this often reduces its competitiveness as a product, particularly in industrially developed markets; therefore, a quiet product is the best marketing argument. Therefore, reducing the noise levels of machines and equipment is significant for economic and social development and greatly influences the improvement of the competitive advantage of the economy, the quality of life and sustainable development. To manufacture a quiet machine or reduce existing noise, one must be able to identify, locate, define and describe noise source in terms of time and frequency domains. To describe noise source one must know how to define the source of a noise, which means to know its sound power, radiation pattern and spectrum, and duration in time domain. Legislation stipulates the compulsory reduction of excessive noise levels, typically at source. To be able to reduce the source of noise, one must know the mechanisms of noise generation, which are often different in different types of machines and equipment, different modes of operation, and therefore often also different during duration of operation. Complex sources of noise greatly complicate the issue when the main source of noise cannot be simply determined. When and if we are aware of the main source of noise, the problem lies in how to reduce noise without changing the machine’s characteristics. To reduce noise at source, we look for the mechanisms that cause noise and have the greatest influence on total noise level. The programme group primarily deals with detecting and describing noise generation mechanisms and implementing acquired knowledge to reduce noise from existing sources and develop new products. Special emphasis is given to mechanisms of noise generation in power machinery (fans, compressors, pumps, turbines and IC engines) and electric motors, which have a typical noise spectrum with pronounced tones in the frequency domain. In addition, great attention is also given to impulse sources of noise (due to impacts, gunshot and explosions) with a typical peak in time domain. This is also due to the fact that with impulse effects, restitution time can be over five times longer that with exposure to continuous noise or traffic noise. Impulse noise has also been a focus in terms of assessing its influence on hearing defects or changes in the hearing threshold of workers in manufacturing. The programme group also devotes a great deal of attention to the use of audible sound for monitoring processes and flow phenomena in process engineering, evaluating technological procedures (welding, cutting and other work processes) and product quality control.
Significance for science
The significance of research conducted by the programme group for the development of science is evident from numerous publications in domestic and particularly international reviewed journals, which has also resulted in over 450 citations of the group in published works in the last 10 years. Some of the published works were subject to scientific discussion and testing in internationally recognised laboratories and institutes, for example of the leader of the programme group regarding the use of sound to detect cavitation in water machinery (pumps and turbines). The programme group has become internationally recognised, which is also confirmed by numerous invitations to lecture at foreign universities, give introductory lectures at international conferences, membership in international professional bodies and organisation of major international conferences and summer schools in the field of acoustics, noise and vibrations, including EAA EUROREGIO 2010 congress, which took place between 15 and 18 September 2010, with more than 400 participants, and the international summer school held between 13 and 18 September 2010 in Ljubljana, where 170 participants could listen to 25 prominent lecturers from across Europe. The Research Group Technical Acoustics (FME) main contributions to science concern describing mechanisms of noise generation in the area of power turbo machinery (cavitation, appearance of rotating stall and surge) and active noise control. In addition, the group has made relevant contributions to monitoring cavitation in pumps (also in situ operation) and quality control of welds by using sound in the audible spectrum, and quenching process of steel by using ultrasound. The Research and Development Group (DOMEL) contributed to science in the area of developing environment-friendly products by conducting complex research on suction units and electric motors and by using original methods and procedures for fast optimisation of new products and their improvements in terms of performance, noise and manufacturing costs, which has significantly improved their ability to respond to the dynamic demanding markets, and consequently the competitiveness in demanding global markets. The research group of Occupational Safety (IOS) has contributed to science particularly with regard to classifying incoherent sources of noise and their impact within total noise level of complex (multi-) sources of noise by measuring at emission and immission sites and by inventing the appropriate algorithm. Furthermore, they have contributed significant findings relating to the impact of impulse (normal and high-energy) noise on people (particularly on workers in industrial facilities) and in the area of extra-aural effects of noise on people.
Significance for the country
The results of the research of the programme group are regularly implemented in practice on various levels. Among these, two areas are most pronounced: 1. Implementation of research on the suction unit for wet suction and 2. Development of the acoustic camera or acoustic radar. 1.1. The results of the research on the development of suction units for wet suction that were developed under the auspices of the Technical acoustic research group (FME) are regularly implemented in the production programme of the DOMEL factory from Železniki. A new design of the suction unit rotor which has triangle rotor blade channels and which at the same time rotates much faster than the older version, was implemented. This solution improved energetic and sound characteristics of the suction unit and at the same time reduced the dimensions and the weight of the unit. Use of materials and production costs also decreased. The unit had already been validated and is currently in the prototype stage. Its market share is expected to further increase which is currently over 67% in the European market and over 40% in the world market despite the international competition. Increased market share does not only result in preserving jobs, but also in creating new ones. 1.2. A new electrical motor with the possibility of rotation frequencies up to 100,000 min has been developed by Research and Development Group (DOMEL), which will be used in driving fast suction units of the new generation or units of small dimensions. 2.1. Implementation of research results in the field of development of an acoustic camera, which was developed by Technical acoustic research group (FME) for a foreign client (see item 3 in previous chapter and contract no. 5/072-2013). The software of the new acoustic camera has certain advantages in comparison to the existing ones in the market. Among other things it also enables recording of movable sources of noise in real time. 2.2. The implementation of the research results in the field of the development of an acoustic camera was used for development and manufacturing an ‘acoustic radar’, which enables the recording of the source of noise in the 360 circle and is useful in measuring noise in the environment. The development and production of prototypes was supported by foreign partners (consortium from Austria, Switzerland and Germany), (Contract no. 5/19-2014 from 2014).
Most important scientific results
Annual report
2013,
2014,
2015,
final report
Most important socioeconomically and culturally relevant results
Annual report
2013,
2014,
2015,
final report
