Wyniki wyszukiwania - BazTech

1

The impact of electromagnetic radiation on the degradation of magnetic ferrofluids

Pavlík M., Kruželák L., Mikita M., Špes M., Bucko S., Lisoň L., Kosterec M., Beňa L., Liptai P.

Archives of Electrical Engineering

|

2017

|

Vol. 66, nr 2

361--369

EN

This article deals with magnetic nano-fluids, which are the part of transformer oil ITO 100 and their behavior is influenced by a permanent magnetic field. We performed an IRC analysis in the time domain on the three different samples. Measurements were made before and after radiation of an electromagnetic field. The main objective was to examine changes in the properties of the samples due to the influence of the electromagnetic field. The measurements depend on the orientation of the external magnetic field. This behavior occurs especially during the structuring of the nanoparticles in the sample exposed to the magnetic field. These processes change the polarization of the liquid because the nanoparticles concentration is contained in the fluid.

2

Proposal of the sound insulating measures for a vibrational sorter and verification of the measured effectiveness

Liptai P., Moravec M., Lumnitzer E., Gergeľová M.

Advances in Science and Technology. Research Journal

|

2017

|

Vol. 11, no 3

196--203

EN

The paper describes a specific design of the sound insulating enclosure of a vibrating sorter. Recycling aspects have been taken into account when designing the enclosure, because recycled foam has been applied as a sound-absorbing material. An acoustic camera was used to measure, analyze, evaluate and to localise and identify sound sources. The visualization method was used to locate the critical locations of the device and then quantify them. To evaluate the effectiveness of the proposed enclosure, the measurements of the sound parameters were performed before and after the realization soundproofing measure. The measured results show the requested efficiency of the sound insulating enclosure in terms of noise reduction as well as dust near the sorter.

3

Design and effectiveness verification of sound reduction measures in production hall

Moravec M., Liptai P., Dzuro T., Badida M.

Advances in Science and Technology. Research Journal

|

2017

|

Vol. 11, no 4

220--224

EN

The main aim of the work described in this paper was to design and validate measures to reduce noise levels in a training center. This training center serves for the practical training of students with the focus in the shaping and machining engineering products. Reduction of noise in the training center was mainly due to the clarity and hearing of the spoken word between the lecturer and students, as well as to reduce the risk of hearing damage. In order to reduce noise levels, it was proposed to overlap the training center with a roof structure filled with sound absorbing material in two solutions. The noise absorption coefficient of the selected material was determined on the impedance tube. For verification of effectiveness, measurements of equivalent A sound levels were made before and after realization noise reduction measures. Reduction of equivalent A sound pressure levels after the noise reduction measures are between 15.5 dB and 17.5 dB depending on the measuring point and the operating mode. The effectiveness of the implemented measures reaches a good level, as noise was reduced to the recommended legislative level.